Lesson 9.1: Circle, Triangle, Square, and Rectangle Properties
Examine sides, corners, and properties of 2D shapes.
⏱️ Reading Time: 15 mins
• ❓ 50 Interactive Practice Questions
#2DShapes #CircleSquareTriangleRectangle #SidesAndCorners
Circle, Triangle, Square & Rectangle (Properties & Sides)
Flat 2D shapes are drawn on paper and have height and width, but no depth or thickness.
Circle (0 sides)
Triangle (3 sides)
Square (4 equal)
Rectangle
2D Shapes: Circle, Triangle, Square, and Rectangle.
1. Sides and Corners
• Circle: 1 curved boundary, 0 straight sides, 0 corners.
• Triangle: 3 straight sides, 3 corners.
• Square: 4 straight sides (all equal in length), 4 square corners.
• Rectangle: 4 straight sides (opposite sides are equal), 4 square corners.
Corner (Vertex): The sharp point where two sides meet.
2. Spotting 2D Shapes Around Us
Look around you right now! The door is a rectangle, the chess board is a square, the clock is a circle, and a slice of pizza is a triangle.
Fun Fact: Every square is a special kind of rectangle, but not every rectangle is a square!
💡 Key Learning Takeaways
- Circles have 0 straight sides and 0 corners.
- Triangles have 3 sides; Squares have 4 equal sides.
- Rectangles have opposite sides equal.
🎯 Key Learning Takeaways
2D shapes and attributes.
📄 Printable Worksheets (10 Available)
Download ready-to-print PDFs for offline student practice with separate parent/teacher answer keys.
WL-G2-C09-W10
A4 • 15 Qs
2D Shapes — Worksheet 10
Curriculum Excellence & Final Review
WL-G2-C09-W09
A4 • 15 Qs
2D Shapes — Worksheet 9
Mastery Assessment & Progress Check
WL-G2-C09-W08
A4 • 15 Qs
2D Shapes — Worksheet 8
Mixed Review & Reinforcement
WL-G2-C09-W07
A4 • 15 Qs
2D Shapes — Worksheet 7
Everyday Applications & Story Maths
WL-G2-C09-W06
A4 • 15 Qs
2D Shapes — Worksheet 6
Critical Thinking & Deep Understanding
WL-G2-C09-W05
A4 • 15 Qs
2D Shapes — Worksheet 5
Speed Challenge & Quick Check
WL-G2-C09-W04
A4 • 15 Qs
2D Shapes — Worksheet 4
Problem Solving & Real-Life Stories
WL-G2-C09-W03
A4 • 15 Qs
2D Shapes — Worksheet 3
Hands-on Visual Activity & Matching
WL-G2-C09-W02
A4 • 15 Qs
2D Shapes — Worksheet 2
Essential Practice & Skill Builder
WL-G2-C09-W01
A4 • 15 Qs
2D Shapes — Worksheet 1
Foundational Concepts & Visual Exploration
✍️ Lesson Practice Questions (50 Questions)
Solve these real-world challenges online, test your understanding, and reveal instant step-by-step explanations.
1
Multiple Choice
Hard
1 Mark
What is the difference between (54 + 10) and (42 + 10)?
A
22
B
12
C
54
D
42
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
12
Step-by-Step Explanation:
Adding 10 to both numbers does not change their difference: (54 + 10) - (42 + 10) = 54 - 42 = 12.
2
Multiple Choice
Hard
1 Mark
A secret number plus 12 equals 54. If you double the secret number, what is the result?
A
42
B
108
C
44
D
84
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
84
Step-by-Step Explanation:
The secret number is 42. Doubling it gives 42 × 2 = 84.
3
Multiple Choice
Hard
1 Mark
If 42 + 12 = 54, what is 12 + 42?
A
54
B
42
C
55
D
12
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
54
Step-by-Step Explanation:
The order of addends does not affect the sum (commutative property).
4
Multiple Choice
Hard
1 Mark
Why is 54 greater than 42?
A
Because {v1} is an even number
B
Because {tot} has a bigger first digit
C
Because 54 includes 42 plus an additional 12 items
D
Numbers ending in 0 are always smaller
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because 54 includes 42 plus an additional 12 items
Step-by-Step Explanation:
Adding a positive quantity always increases the total.
5
Multiple Choice
Medium
1 Mark
Sam evaluated 54 - 12 and wrote 66. What was Sam's mistake?
A
He divided the numbers
B
He added instead of subtracting
C
He forgot the units place
D
He multiplied by 2
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
The minus sign means subtraction (taking away), but Sam performed addition.
6
Multiple Choice
Medium
1 Mark
A student claimed that 42 + 12 = 64 because 'we must add 10 to every answer'. Why is this student wrong?
A
Addition is only for 1-digit numbers
B
Addition means combining only the given numbers without adding extra amounts
C
The student subtracted instead
D
The answer is 0
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Addition means combining only the given numbers without adding extra amounts
Step-by-Step Explanation:
42 + 12 equals exactly 54.
7
Multiple Choice
Medium
1 Mark
Complete the pattern: 42, 47, 52, [ ? ].
A
56
B
54
C
57
D
62
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
57
Step-by-Step Explanation:
The pattern increases by 5. 52 + 5 = 57.
8
Multiple Choice
Medium
1 Mark
Find the missing number: 42 + [ ? ] = 54.
A
11
B
12
C
13
D
42
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
12
Step-by-Step Explanation:
Missing value is 12 because 42 + 12 = 54.
9
Multiple Choice
Medium
1 Mark
In a school garden, there are 42 yellow marigolds and 12 purple petunias. How many flowers are blooming in total?
A
54 flowers
B
42 flowers
C
59 flowers
D
12 flowers
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
54 flowers
Step-by-Step Explanation:
42 + 12 = 54 flowers.
10
Multiple Choice
Medium
1 Mark
A school library received 54 new graphic novels. Students checked out 12 novels on Monday. How many new novels are still on the shelf?
A
54 novels
B
42 novels
C
43 novels
D
12 novels
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
42 novels
Step-by-Step Explanation:
54 - 12 = 42 novels remaining.
11
Multiple Choice
Medium
1 Mark
A baker packed 42 apple pies in the morning and 12 cherry pies in the afternoon. How many pies did the baker pack in all?
A
56 pies
B
54 pies
C
42 pies
D
52 pies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
54 pies
Step-by-Step Explanation:
42 + 12 = 54 pies in total.
12
Multiple Choice
Easy
1 Mark
What number is 10 more than 42?
A
32
B
52
C
62
D
43
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
52
Step-by-Step Explanation:
42 + 10 = 52.
13
Multiple Choice
Easy
1 Mark
Which comparison is correct: 54 [ ? ] 49?
A
=
B
>
C
≈
D
<
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
54 is greater than 49.
14
Multiple Choice
Easy
1 Mark
Calculate: 54 - 12 = ?
A
41
B
42
C
43
D
12
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
42
Step-by-Step Explanation:
54 - 12 = 42.
15
Multiple Choice
Easy
1 Mark
In Chapter '2D Shapes', calculate: 42 + 12 = ?
A
54
B
55
C
64
D
53
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
54
Step-by-Step Explanation:
42 + 12 = 54.
16
Multiple Choice
Hard
1 Mark
What is the difference between (69 + 10) and (35 + 10)?
A
35
B
69
C
34
D
44
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
34
Step-by-Step Explanation:
Adding 10 to both numbers does not change their difference: (69 + 10) - (35 + 10) = 69 - 35 = 34.
17
Multiple Choice
Hard
1 Mark
A secret number plus 34 equals 69. If you double the secret number, what is the result?
A
70
B
37
C
138
D
35
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
70
Step-by-Step Explanation:
The secret number is 35. Doubling it gives 35 × 2 = 70.
18
Multiple Choice
Hard
1 Mark
If 35 + 34 = 69, what is 34 + 35?
A
70
B
69
C
34
D
35
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
69
Step-by-Step Explanation:
The order of addends does not affect the sum (commutative property).
19
Multiple Choice
Hard
1 Mark
Why is 69 greater than 35?
A
Because 69 includes 35 plus an additional 34 items
B
Because {tot} has a bigger first digit
C
Because {v1} is an even number
D
Numbers ending in 0 are always smaller
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because 69 includes 35 plus an additional 34 items
Step-by-Step Explanation:
Adding a positive quantity always increases the total.
20
Multiple Choice
Medium
1 Mark
Sam evaluated 69 - 34 and wrote 103. What was Sam's mistake?
A
He divided the numbers
B
He added instead of subtracting
C
He multiplied by 2
D
He forgot the units place
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
The minus sign means subtraction (taking away), but Sam performed addition.
21
Multiple Choice
Medium
1 Mark
A student claimed that 35 + 34 = 79 because 'we must add 10 to every answer'. Why is this student wrong?
A
Addition means combining only the given numbers without adding extra amounts
B
The answer is 0
C
The student subtracted instead
D
Addition is only for 1-digit numbers
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Addition means combining only the given numbers without adding extra amounts
Step-by-Step Explanation:
35 + 34 equals exactly 69.
22
Multiple Choice
Medium
1 Mark
Complete the pattern: 35, 40, 45, [ ? ].
A
55
B
50
C
49
D
47
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
50
Step-by-Step Explanation:
The pattern increases by 5. 45 + 5 = 50.
23
Multiple Choice
Medium
1 Mark
Find the missing number: 35 + [ ? ] = 69.
A
35
B
34
C
33
D
35
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
34
Step-by-Step Explanation:
Missing value is 34 because 35 + 34 = 69.
24
Multiple Choice
Medium
1 Mark
In a school garden, there are 35 yellow marigolds and 34 purple petunias. How many flowers are blooming in total?
A
69 flowers
B
35 flowers
C
74 flowers
D
34 flowers
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
69 flowers
Step-by-Step Explanation:
35 + 34 = 69 flowers.
25
Multiple Choice
Medium
1 Mark
A school library received 69 new graphic novels. Students checked out 34 novels on Monday. How many new novels are still on the shelf?
A
36 novels
B
69 novels
C
35 novels
D
34 novels
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
35 novels
Step-by-Step Explanation:
69 - 34 = 35 novels remaining.
26
Multiple Choice
Medium
1 Mark
A baker packed 35 apple pies in the morning and 34 cherry pies in the afternoon. How many pies did the baker pack in all?
A
67 pies
B
71 pies
C
35 pies
D
69 pies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
69 pies
Step-by-Step Explanation:
35 + 34 = 69 pies in total.
27
Multiple Choice
Easy
1 Mark
What number is 10 more than 35?
A
25
B
45
C
36
D
55
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
45
Step-by-Step Explanation:
35 + 10 = 45.
28
Multiple Choice
Easy
1 Mark
Which comparison is correct: 69 [ ? ] 64?
A
≈
B
<
C
>
D
=
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
69 is greater than 64.
29
Multiple Choice
Easy
1 Mark
Calculate: 69 - 34 = ?
A
36
B
34
C
34
D
35
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
35
Step-by-Step Explanation:
69 - 34 = 35.
30
Multiple Choice
Easy
1 Mark
In Chapter '2D Shapes', calculate: 35 + 34 = ?
A
79
B
70
C
69
D
68
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
69
Step-by-Step Explanation:
35 + 34 = 69.
31
Multiple Choice
Hard
1 Mark
What is the difference between (59 + 10) and (28 + 10)?
A
41
B
31
C
28
D
59
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
31
Step-by-Step Explanation:
Adding 10 to both numbers does not change their difference: (59 + 10) - (28 + 10) = 59 - 28 = 31.
32
Multiple Choice
Hard
1 Mark
A secret number plus 31 equals 59. If you double the secret number, what is the result?
A
56
B
30
C
118
D
28
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
56
Step-by-Step Explanation:
The secret number is 28. Doubling it gives 28 × 2 = 56.
33
Multiple Choice
Hard
1 Mark
If 28 + 31 = 59, what is 31 + 28?
A
28
B
31
C
59
D
60
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
59
Step-by-Step Explanation:
The order of addends does not affect the sum (commutative property).
34
Multiple Choice
Hard
1 Mark
Why is 59 greater than 28?
A
Because 59 includes 28 plus an additional 31 items
B
Numbers ending in 0 are always smaller
C
Because {tot} has a bigger first digit
D
Because {v1} is an even number
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because 59 includes 28 plus an additional 31 items
Step-by-Step Explanation:
Adding a positive quantity always increases the total.
35
Multiple Choice
Medium
1 Mark
Sam evaluated 59 - 31 and wrote 90. What was Sam's mistake?
A
He multiplied by 2
B
He added instead of subtracting
C
He divided the numbers
D
He forgot the units place
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
The minus sign means subtraction (taking away), but Sam performed addition.
36
Multiple Choice
Medium
1 Mark
A student claimed that 28 + 31 = 69 because 'we must add 10 to every answer'. Why is this student wrong?
A
The answer is 0
B
The student subtracted instead
C
Addition means combining only the given numbers without adding extra amounts
D
Addition is only for 1-digit numbers
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Addition means combining only the given numbers without adding extra amounts
Step-by-Step Explanation:
28 + 31 equals exactly 59.
37
Multiple Choice
Medium
1 Mark
Complete the pattern: 28, 33, 38, [ ? ].
A
48
B
42
C
43
D
40
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
43
Step-by-Step Explanation:
The pattern increases by 5. 38 + 5 = 43.
38
Multiple Choice
Medium
1 Mark
Find the missing number: 28 + [ ? ] = 59.
A
28
B
30
C
32
D
31
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
31
Step-by-Step Explanation:
Missing value is 31 because 28 + 31 = 59.
39
Multiple Choice
Medium
1 Mark
In a school garden, there are 28 yellow marigolds and 31 purple petunias. How many flowers are blooming in total?
A
64 flowers
B
59 flowers
C
28 flowers
D
31 flowers
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
59 flowers
Step-by-Step Explanation:
28 + 31 = 59 flowers.
40
Multiple Choice
Medium
1 Mark
A school library received 59 new graphic novels. Students checked out 31 novels on Monday. How many new novels are still on the shelf?
A
28 novels
B
31 novels
C
29 novels
D
59 novels
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
28 novels
Step-by-Step Explanation:
59 - 31 = 28 novels remaining.
41
Multiple Choice
Medium
1 Mark
A baker packed 28 apple pies in the morning and 31 cherry pies in the afternoon. How many pies did the baker pack in all?
A
61 pies
B
28 pies
C
59 pies
D
57 pies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
59 pies
Step-by-Step Explanation:
28 + 31 = 59 pies in total.
42
Multiple Choice
Easy
1 Mark
What number is 10 more than 28?
A
18
B
48
C
29
D
38
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
38
Step-by-Step Explanation:
28 + 10 = 38.
43
Multiple Choice
Easy
1 Mark
Which comparison is correct: 59 [ ? ] 54?
A
<
B
≈
C
>
D
=
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
59 is greater than 54.
44
Multiple Choice
Easy
1 Mark
Calculate: 59 - 31 = ?
A
28
B
31
C
27
D
29
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
28
Step-by-Step Explanation:
59 - 31 = 28.
45
Multiple Choice
Easy
1 Mark
In Chapter '2D Shapes', calculate: 28 + 31 = ?
A
58
B
69
C
60
D
59
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
59
Step-by-Step Explanation:
28 + 31 = 59.
46
Multiple Choice
Hard
1 Mark
What is the difference between (49 + 10) and (21 + 10)?
A
49
B
21
C
38
D
28
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
28
Step-by-Step Explanation:
Adding 10 to both numbers does not change their difference: (49 + 10) - (21 + 10) = 49 - 21 = 28.
47
Multiple Choice
Hard
1 Mark
A secret number plus 28 equals 49. If you double the secret number, what is the result?
A
21
B
98
C
23
D
42
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
42
Step-by-Step Explanation:
The secret number is 21. Doubling it gives 21 × 2 = 42.
48
Multiple Choice
Hard
1 Mark
If 21 + 28 = 49, what is 28 + 21?
A
49
B
21
C
50
D
28
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
49
Step-by-Step Explanation:
The order of addends does not affect the sum (commutative property).
49
Multiple Choice
Hard
1 Mark
Why is 49 greater than 21?
A
Because {tot} has a bigger first digit
B
Because 49 includes 21 plus an additional 28 items
C
Numbers ending in 0 are always smaller
D
Because {v1} is an even number
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because 49 includes 21 plus an additional 28 items
Step-by-Step Explanation:
Adding a positive quantity always increases the total.
50
Multiple Choice
Medium
1 Mark
Sam evaluated 49 - 28 and wrote 77. What was Sam's mistake?
A
He multiplied by 2
B
He divided the numbers
C
He added instead of subtracting
D
He forgot the units place
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
The minus sign means subtraction (taking away), but Sam performed addition.