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

Approved by eNotes Editorial Team

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial