x+x+90=180
x+x+90=1802x+90=180
x+x+90=1802x+90=1802x=180-90
x+x+90=1802x+90=1802x=180-902x=90
x+x+90=1802x+90=1802x=180-902x=902x/2x =90/2
x=45
9y+9y+90=180
18y+90=180
18y=180-90
18y=90
18y/18 =90/18
y=5
