What is the value of z?

z = 61

Step-by-step explanation:

The exterior angle is congruent (equal to) the sum of the 2 farthest angles from it, so you can set the equation like this:

z + z - 11 = z + 50

Add like terms, which would be the 2 "z's" on the left side:

2z - 11 = z + 50

Then subtract the z on the right side from both sides:

2z - 11 = z + 50

-z          -z

z - 11 = 50

Add 11 to both sides:

z - 11 = 50

  + 11    +11

z = 61

a

step-by-step explanation: