Solve the following for X and Y: 2y+4x=14 and x-y=-1

Firstly, Take equation 1 (2y+4x=14) and divide it all by 2. This gives y+2x=7. Next make Y the 'subject' AKA put it on it's own. To do this Subtract 2x from both sides. Now we have Y=7-2X. Here you can see Y and 7-2x are exactly the same (hence the = sign).

Now get equation 2 and substitute in the 7-2x for Y since they are the same. so x-y=-1 goes to x-(7-2x)=-1. Expanding this gives x-7+2x=-1 which gives 3x-7=-1. Add 7 to both sides 3x=6 so x=2. Sub x=2 into x-y=-1.... 2-y=-1. Add y to both sides and add one to both sides. y=3.

Final answer is Y=3 and x=2

TM

Related Maths GCSE answers

All answers ▸

x : y = 11 : 3 x + y = 140 Find x and y


Given the curve y=x^2 +1 and the line y=k, find, using graphical methods only, the value of k for which there is exactly one solution.


How to solve rates of change questions?


Given the curve y=x^2 -6x +8, find the turning point.