Verified answer

Solve for one variable first. So the easiest is: x+.5y=9

Solve for x: x=9-.5y

Substitute into other formula: x/8+y/5=2.5

(9-.5y)/8 + y/5 =2.5

Get rid of fraction by multiplying by 40 (8x5)

[(9-.5y)/8 x 40] + [y/5 x 40] = 2.5

This gets you:

(9-.5y)(5) + (8y) = 100

Solve for y:

45-2.5y+8y=100

5.5Y=55

So y=10

Substitute back into first formula: x +.5y=9

X+.5(10)=9

X+5=9

So x =4