Looking at the given diagram,
angle 9x - 1 and angle y - 20 are linear pairs. they lie on a straight line. The sum of the angles on a straight line is 180 degrees. It means that
9x - 1 + y - 20 = 180
y = 180 + 1 + 20 - 9x
y = 201 - 9x equation 1
Also, angle 5x - 15 and angle y - 20 are vertically opposite angles. Vertically opposite angles are equal. It means that
5x - 15 = y - 20 equation 2
Substituting equation 1 into equation 2, it becomes
5x - 15 = 201 - 9x - 20
Collecting like terms, it becomes
5x + 9x = 201 - 20 + 15
14x = 196
x = 196/14
x = 14
y = 201 - 9x = 201 - 9 * 14
y = 201 - 126
y = 75+