Question

Find the value of x.

Answer 1

180=65+x+x-5
180=60+2x
120=2x
60=x

(x-5)
(60-5)=55

65+60+55=180

Answer 2

We know:

The sum of the measures of the angles is equal 180°.

Therefore we have the equation:

$x+(x-5)+65=180\\\\x+x-5+65=180\\\\(x+x)+(-5+65)=180\\\\2x+60=180\ \ \ \ |\text{subtract 60 from both sides}\\\\2x=120\ \ \ \ |\text{divide both sides by 2}\\\\\boxed{x=60}$