Question

1) In the diagram, l || m. If the measure of angle 3 is 120 find the measure of the following angles

a) angle 4

b) angle 6

c) angle 8

Answer 1

a) 60° , b) 120° and c) 60°

Explanation:

See the diagram attached to this question.

a) Here, ∠ 4 and ∠ 3 are supplementary angles.

So, ∠ 4 + ∠ 3 = 180° {Here, ∠ 3 is given to be 120°}

⇒ ∠ 4 = 180° - ∠ 3 = 180° - 120° = 60° (Answer)

b) Now, ∠ 3 and ∠ 6 are alternate angles and hence, ∠ 3 = ∠ 6 = 120° (Answer)

c) Here, ∠ 6 and ∠ 8 are supplementary angles.

So, ∠ 6 + ∠ 8 = 180°

⇒ ∠ 8 = 180° - ∠ 6 = 180° - 120° = 60° (Answer)