Someone who can help would be great.

Answer:
x=5
Step-by-step explanation:
In a square, the diagonals are equal.
4x+17 = 12x-23
Subtract 4x from each side.
4x-4x+17 = 12x-4x-23
17 = 8x-23
Add 23 to each side
17+23 = 8x-23+23
40 = 8x
Divide each side by 8
40/8 = 8x/8
5 =x