To solve a simultaneous equation you should number your equations and re arrange one of them to make y the subject. (You could do it the other way and find the expression for x first)3x + y = 11 [1] and 2x + y = 8 [2]. Re arranging equation [1] we will get the following equation by subtracting 3x from both sides. y = 11 - 3x. Then by substituting the expression for y into equation [2] you can solve for x, giving x = 3. Then we can find the value of y by substituting the value we found for x into equation [1]3(3) + y = 11. 9 +y = 11, giving y =2