Both sides need to equal 180 (The side with the 90 degrees measurement and the side with equations). So first subtract 180 from 90
[tex]180 - 90[/tex]
to get the measurement of 5x and you get 90 but we aren't done yet since we need to find x so now we need to divide 5 by 90
[tex]90 \div 5 = 18[/tex]
and we get 18 which is X.
[tex]x = 18[/tex]
Now we need to find the measurement of Y. Now both angles on that side together equals 180 so we need this equation.
[tex]5(y + 11) + 4y - 10 = 180[/tex]
First, distribute 5(y + 11)
[tex]5 \times y \\ 5 \times 11[/tex]
Then you get this equation :
[tex]5y + 55 + 4y - 10 = 180[/tex]
Now, add the two equations together
[tex]5y + 55 + 4y - 10[/tex]
and you get this equation
[tex]9y + 45 = 180[/tex]
Now subtract 45 from both sides
[tex]9y + 45 - 45 = 180 - 45[/tex]
and divide by 9 on both sides
[tex]9y \div 9 = 135 \div 9[/tex]
and you get your answer
[tex]y = 15[/tex]
So
[tex]x = 18[/tex]
and
[tex]y = 15[/tex]
