Geometry math question no guessing and show work

Here we have to use the theorem tht exterior angle is the sum of non adjacent interior angles. That is ,

z = x+y

And the values of x,y and z are given in terms of n. On substituting these values for x,y and z, we will get

151-5n = 4n-18+n+9

Combining like terms of the right side

151-5n = 5n -9

Moving 5n to the right side and 9 to the left side,

151+9 = 5n+5n

160=10n

Dividing both sides by 10

n = 16

Now we need to find the value of z when n =16. SO we substitute the value of n in z, that is

z =151-5(16) =151-80 = 71 degree .

So the correct option is A

i need the table so i can see

step-by-step explanation: