Step-by-step explanation:
4x+9y=28
-4x-y=-28
8y=0
divide both side by 8
y=0
solve for X in equation 1
4(X)-9(0)=28
4x-0=28
4x =28
divide both side by 4
4x/4=28/4
X= 7
y=0,x=7
