x = 3y - 8
Plug this in for variable x in equation [2]
[2] 3•(3y-8) + 2y = 31
[2] 11y = 55
Solve equation [2] for the variable y
[2] 11y = 55
[2] y = 5 // By now we know this much :
x = 3y-8
y = 5// Use the y value to solve for x
x = 3(5)-8 = 7 Solution :
{x,y} = {7,5}
Processing ends successfully