Question

Two angles whose measures are a & b are such that 2a - 3b = 60${}^{\circ }$ then 5b =

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degrees, if they form a linear pair.

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${}^{\circ }$