Answer:
9
Step-by-step explanation:
(x+3)/8 = (x+6)/10
x+3 = 8(x+6)/10
x+3 = 4(x+6)/5
x+3 = (4x+24)/5
x +3 = 4x/5 + 24/5
x - 4x/5 = (24/5)-3
x/5 = 9/5
x = 9
