Let us start first writing the equation separately: Equation 1: x+y=8 Equation 2: x+7y=8 Let us subtract Equation 1 from Equation 2 x+y=8 -(x+7y)=8 ------------------ 0 -6y=0 6y=0 y=0 Now we have y=0, let us put this in any of the equation 1 or equation 2 Let us first put it in Equation 1 x+y=8 x+0=8---putting y value as y=0 x=8 Now Equation 2: x+7y=8 x+7(0)=8 x+0=8 x=8