Answer: x = 25
Explanation:
This appears to be an equilateral triangle. All angles are shown to be the same. This means all 3 sides will have the same length:
3x-5
4x-30
2x+20
are all equal to each other.
3x-5 = 4x-30
x = 25
----
3x-5 = 70
4x-30 = 70
2x+20 = 70