9a-9 ;9a+18 is the angles are supplementary ,find their measures

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Two Angles are Supplementary if they add up to 180 degrees.

So (9a-9) + (9a +18) should add up to 180 degrees

9a-9 + 9a+18= 180

group similar factors together

9a+9a =180-9

18a = 171

divide by 18 both sides

a = 171/18

a = 9.5

then the first angle is 9a-9 = 9x9.5 -9= 85.5-9= 76.5 degress

then the other angle would be 180-76.5 = 103.5 degrees

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Approved by eNotes Editorial Team