3x = 8y + 11
x + 6y - 8 = 0...which can be written as x = -6y + 8
We now have both equations in the same format. It can be seen that we can make the coefficients of x equal in both equations by multiplying the 2nd equation by 3.
3x = 8y + 11
3x = -18y + 24
If the "lower" equation is then subtracted from the "upper" equation - this eliminates x.
3x - 3x = 8y -(-18y) + 11 - 24
0 = 26y - 13...which can be written as 26y = 13 ; thus y = 13/26 = 1/2 Now substitute for y in either of the original equations to determine x.
3x = (8 x 1/2) + 11 : 3x = 4 + 11 = 15 : X = 15/3 = 5
x + 6y - 8 = 0...which can be written as x = -6y + 8
We now have both equations in the same format. It can be seen that we can make the coefficients of x equal in both equations by multiplying the 2nd equation by 3.
3x = 8y + 11
3x = -18y + 24
If the "lower" equation is then subtracted from the "upper" equation - this eliminates x.
3x - 3x = 8y -(-18y) + 11 - 24
0 = 26y - 13...which can be written as 26y = 13 ; thus y = 13/26 = 1/2 Now substitute for y in either of the original equations to determine x.
3x = (8 x 1/2) + 11 : 3x = 4 + 11 = 15 : X = 15/3 = 5