Answer:
x = -6
Step-by-step explanation:
All three angles are equal, so all three sides are equal, making this an equilateral triangle
5x+10 = 2x-8
Subtract 2x from each side
5x-2x +10 = 2x-8-2x
3x+10 = -8
Subtract 10 from each side
3x+10-10 = -8-10
3x = -18
Divide by 3
3x/3 = -18/-3
x = -6
