Answer:
135
Step-by-step explanation:
6 x 2.5 = 15/2 = 7.5 x 2 = 15
8 x 6 = 48 + 15 = 63
8 x 2.5 = 20 + 63 = 83
6.5 x 8 = 52 + 83 = 135
Yes, you can use similar triangles to find x
1/2b=-4+16
1/2b= 12
b=12×2
b=24