Solve the simultaneous equations 2x - 3y = 7 and 3x + 4y = 2. Do not use trail and improvement.

[ 2x - 3y = 7 ] *3 = [ 6x - 9y = 21 ]

[ 3x + 4y = 2 ] *2 = [ 6x + 8y = 4 ]

[ 6x + 8y = 4 ] - [ 6x - 9y = 21 ] = [ 17y = -17 ] 

Therefore, y = -1.

Substituting y = -1 into the original equations and solving for x we get the following.

2x + 3 = 7

2x = 4

x = 2

And,

3x - 4 = 2

3x = 6

x = 2

So we have x = 2 and y = -1.

Answered by Elizabeth H. Maths tutor

13459 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations: 2x-3y = 24 and 6x+2y = -5


How to find conditional probability


write 36 as a product of its prime factors


Solve the following quadratic simultaneous equation: y = x + 4 and y = x^2 + 4x


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences