Answer:
x = -7
Explanation:
You want to know the value of x given a triangle with exterior angle 130° and remote interior angles of 51° and (-8x+23)°.
Exterior angle
The measure of the exterior angle (130°) is the sum of the remote interior angles, 51° and (-8x+23)°.
130 = 51 +(-8x +23)
56 = -8x . . . . . . . . . . . subtract 74
-7 = x . . . . . . . . . . . divide by -8
The value of x is -7.