Question

Two angles whose measures are a & b are such that 2a - 3b = 60${}^{\circ }$ and they form a linear pair. Then, the degree measure of 5b =

___

Answer 1

Given that,

2a - 3b = 60${}^{\circ }$

Also if they form a linear pair, then

2 × (180${}^{\circ }$ - b) - 3b = 60${}^{\circ }$ ( since a = 180${}^{\circ }$ - b)

⇒ 360${}^{\circ }$ - 2b - 3b = 60${}^{\circ }$

⇒ 5b =300${}^{\circ }$