Solve the simultaneous equations equation 1: 2x+3y=4 and equation 2: 5x+6y=7

This question can be solved by many methods but the elimination method is the fastest one in this case.  The unknown that will be eliminated is y. Equation 1 is multiplied by 2 to give 4x+6y=8. Since I have chosen to eliminate y, I will now subtract equation 1 from equation 2 as this will leave us with the x as the only unknown. So:  5x+6y-4x-6y=7-8 This gives x=-1 which can be substituted in either of equation 1 or 2 to solve for y. If we substitute in equation 1 we get 2*(-1)+3y=4 so y=2. We can check that the answer is correct by substituting x and y in either equation to confirm that it's equal to the right hand side of the equation.  So for equation 2: 5*(-1)+6*2=7 which is what was expected so the answer is correct.

MP

Related Maths GCSE answers

All answers ▸

Emma has a digital photo. The photo has width 960 pixels and height 720 pixels. Write down the ratio of the width of the photo to the height of the photo. Give the ratio in its simplest form.


Solve the simultaneous equations to find x and y: 3x + 5y = 10 , 5x + 4y = 8


Prove that (2n+3)^2-(2n-3)^2 is a multiple of 8 for positive integer values of n


What is the significance of the number e (Euler's number)?