Solve for x.

25x  - 15   = 60    add 15 to both sides

25x  = 75.......divide both sides by 25

x  = 3

I can solve for x and y here!

This is an equilateral triangle. All angles = 60 degrees. So we know 25x - 15 = 60. To find x, we need to isolate and then divide by the coefficient. To isolate, we add 15. After we do that, we divide by the coefficient, 25. Can you finish it?