Hello from MrBillDoesMath!
Answer:
x = 12
Discussion:
From the diagram, the two triangles appear to be similiar. Then
28/7 = (6x + 28) /25
as the ratio of corresponding parts of similar triangle are the same.
28/7 = (6x +28)/25 => simplify. 28/7 = 4
4 = (6x + 28)/25 => multiply both sides by 25
4*25 = 6x + 28 => simplify, 4 * 25 = 100
100 = 6x + 28 => subtract 28 from both sides
100 -28 = 6x => simplify. 100 - 28 - 72
72 = 6x => divide both sides by 6
72/6 = 12 = x
Thank you,
MrB