Solve the following simultaneous equations: 3x + y = 11 2x + y = 8

Start off by determining which unknowns have the same coefficient-      In this case it would be y as the coefficient of y is 1 in both equationsThen make both equations equal to y-      So 3x+y= 11 would become y= 11-3x2x+y= 8 would become y=8-2xNow that both equations are equal to y, this means the must be equal to each otherso we can re-write the equations like this: -      11-3x=8-2xTo solve for x we need to get all the x's on one side, and all the numbers on the other side-      Because they are equal, what we do to one side we must do to the other-      If we add 3x to each side we will get: 11=8+x-      Then to get all the numbers on the opposite side, we'd need to -8 from both sides, this would give us: 3=xSo now we know x=3, to find y we can substitute x into either of the very first equations-      If we take 2x+y=8 and substitute in x=3: 2(3)+y=8 which is the same as 6+y=8-      Which would mean, y=2So we have our answer, x=3 and y=2-      you can check this by substituting x and y into the other first equation (3x + y = 11)-      3(3) + 2= 9+2 =11

AR
Answered by Amelia R. Maths tutor

4360 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Renee buys 5 kg of sweets to sell. She pays £10 for the sweets. Renee puts all the sweets into bags. She puts 250 g of sweets into each bag. She sells each bag of sweets for 65p. Renee sells all the bags of sweets. Work out her percentage profit.


Expand (X+5)(2X+3)


Find the points that the graph "y = x^2 -4x -14" touches the x-axis


When given an equation with both letters and numbers on each side of the equals sign, for instance 4x +3 = 5x - 3, how do you know what to do first?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning