Solve the following simultaneous equation: 3x+2y=20 and x+4y=20

We are going to try to eliminate one of the variables in one of the equations. This can be done by rearranging the second equation to x=20-4y. And then substituting x into the first equation.3x+2y=20 => 3*(20-4y)+2y=20 => 60-12y+2y=20 Then we separate constants and variables:=> -10y=-40 => y=(-40)/(-10) => y=4We have found y! Now it's easy to find x, using the equation x=20-4y => x=20-4*4 => x=4So the numbers which satisfy the two equations simultaniously are x=4 and y=4.

SK
Answered by Stephanie K. Maths tutor

5402 Views

See similar Maths 13 Plus tutors

Related Maths 13 Plus answers

All answers ▸

Solve for x and y using these simultaneous equations: 2x + 3y = 21, y = 2x - 1


Eleven pet owners were asked how many pets they had in total. The results are given below. 1, 1, 2, 3, 4, 5, 5, 6, 6, 6, 7 - Two more owners are asked how many pets they have. Including their results the mean goes down to 4 but the mode is unchanged from


How do I work out the area of different shapes?


Solve these two equations simultaneously: 7x+y=1 and 2x^2 - y=3


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