Solve the simultaneous equations: 5x + y = 21 and x - 3y = 9

label equation 5x + y = 21 as (1) and equation x - 3y = 9 as (2) multiply equation (2) by 5 to get : 5x - 15y = 9 (3) then subtract equation (1) from equation (2) in order the eliminate the x variable -16y =24 solve for y: y = -3/2 then substitute the value for y =-3/2 into the first equation and solve for x to determine: x=9/2

SG
Answered by Shruti G. Maths tutor

2210 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve 56x + 10 = 60 - 48x


Expand and simplify (x + 5)(x – 1)


How do you solve a set of three similatenous equations with three unknown variables?


What is the equation of the tangent of the circle x^2+y^2=25 at the point (3,4)


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences