Answer is y= 9
Step by step
Your equation, since they are vertical angles they are congruent, or equal
18y - 18 = 16y
Subtract 18y from both sides to combine variables
18y - 18y - 18 = 16y - 18y
-18 = -2y
Divide both sides by -2 to solve for y
-18/-2 = -2/-2 y
9 = y
Check your work
So angle 18y - 18
Substitute 9 for y
18(9) - 18
162 - 18 = 144
The other angle is
16y
16(9) = 144
Since the angles are vertical angles, they are congruent, so their angles will be the same
and they are, they are both 144 degrees.