268,995 views
5 votes
5 votes
< A and < B are supplementary angles. If m m < B= (2x+30), then find the measure of < A.

User DEFL
by
3.0k points

1 Answer

12 votes
12 votes

Answer:

m<A = 50°

Explanation:

supplementary angles add up to 180°

m<B = 2x + 30

we don't know m<A, so we'll say the value of it is x

2x + 30 + x = 180°

3x + 30 = 180

3x = 150

x = 50

plug this value back in for x

m<B = 2(50) + 30 = 130

m<B = 130°

m<A = x = 50

m<A = 50°

to prove these are supplementary angles, 130 + 50 = 180

User Toddcscar
by
3.3k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.