Answer:
x =11
Step-by-step explanation:
XWY + YXZ = XWZ
5x+5 + 2x+8 = 90
Combine like terms
7x+ 13 = 90
Subtract 13 from each side
7x= 90-13
7x = 77
Divide by 7
7x/7 = 77/7
x = 11