Question

If a and b are supplementary angles and m∠a=2x+6and m∠b=x+3,find m∠a

Answer 1

114

Explanation:

Supplementary means that all the angles in your givens add up to 180 degrees.

Givens

<A + <B = 180

<A = 2x + 6

<B = x + 3

Solution

<A + <B = 180 Substitute for <A and <B

2x + 6 + x + 3 = 180 Combine like terms on the left.

3x + 9 = 180 Subtract 9 from both sides

3x = 180 - 9

3x = 171 Divide by 3

x = 171/3

x = 57

That's not your answer.

<A = 2x + 6

<A = 2*57

<A = 114