Answer:
x = -16
Step-by-step explanation:
An exterior angle of a triangle is the angle formed when one side is extended.
The sum of all exterior angles is 360°
Since the 3 exterior angles are given in terms of x we can add them up, set the sum to 360 and solve for x
Adding we get
-9x + 13
-2x + 3
-10x + 8
_________
-21x + 24
_________
∴ -21x + 24 = 360
Subtract 24 from both sides:
-21x = 360-24
-21x = 336
Divide both sides by -21
-21x/-21 = 336/-21
x = -16
Hope that helps. Please ask if you need any more explanation
