Solve the simultaneous equations: 1) 3x+5y=14 and 2) -3y+10=x

  1. Multiple the second equation through by 3 so that the x is multiplied by the same number in both equations. -> -9y + 30 = 3x
    2) Rearrange the equation so that the x and y are both on the same side.
    -> 3x + 9y = 30
    3) Minus the first equation away from the second to remove the x.
    -> 3x + 9y = 30- 3x + 5y = 14
    = 4y = 16
    4) Now divide both sides of the remaining equation to work out y.
    -> y=4
    5) Now replace y with 4 in either equation to find x. (For this example I will use the first equation)
    -> 3x + 5(4) = 14
    3x + 20 = 14
    3x = -6
    x = -2
    so... y=4 and x=-2

GS

Related Maths GCSE answers

All answers ▸

Q: How to solve the simultaneous equations 3x+2y=7 and 5x+y=14


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.


In a sale the price of a shirt is reduced by 60%. The sale price is £7.98. What is the original price?


Sam takes out a £720 loan. Sam will have to pay back the £720 plus an interest rate of 15%. He will have to pay this back in 12 equal monthly instalments. How much must Sam pay monthly?