Answer:
AC = 40
Explanation:
AC and BD are equal to each other in length. So:
4x-4 = 3x+7
Now you solve for x. Add 4 to each side.
4x= 3x + 11
Then subtract 3x from both sides.
X = 11. There you have X, now you plug 11 in for x in the AC= 3x+7
3(11) + 7 = AC
33 + 7 = AC
40 = AC