Lines & Angles — Chapter Test | Class 7 IMO

Q1

Complementary angles add up to ___ ?

Complementary angles add to 90°.

Q2

Supplementary angles add up to ___ ?

Supplementary angles add to 180°.

Q3

Vertically opposite angles are always ___ ?

Vertically opposite angles are equal.

Q4

The angles of a triangle add up to ___ ?

The angle sum of a triangle is 180°.

Q5

What is the complement of 35°?

90 − 35 = 55°.

Q6

What is the supplement of 125°?

180 − 125 = 55°.

Q7

Two angles form a linear pair and one is 70°. What is the other?

180 − 70 = 110°.

Q8

Two angles of a triangle are 50° and 60°. What is the third?

180 − 50 − 60 = 70°.

Q9

Two angles of a triangle are 90° and 30°. What is the third?

180 − 90 − 30 = 60°.

Q10

Two lines cross and one angle is 115°. What is its vertically opposite angle?

Vertically opposite angles are equal, so 115°.

Q11

A ramp makes a 40° angle with the floor. What is its complement?

90 − 40 = 50°.

Q12

Two angles lie on a straight line; one is 65°. What is the other?

180 − 65 = 115°.

Q13

The angles of a triangle are in the ratio 1 : 2 : 3. What is the largest angle?

Parts = 6; 180 ÷ 6 = 30, so angles are 30°, 60°, 90° — the largest is 90°.

Q14

An angle is equal to its own complement. What is the angle?

If x = 90 − x, then 2x = 90, so x = 45°.