Solve these simultaneous equations: 3x-5=-4y and 2xy=-4

First start with 2xy=-4, rearrange to find in terms of x, x=-2/y. Substitute this into the other equation (3x-5=-4y), producing -6/y -5 =-4y.Times every term by -y resulting in 6+5y=4y2 .Rearrange to 4y2-5y-6=0 and solve the quadratic (4y+3)(y-2) = 0 resulting in y=2 or y=-3/4.Substitute into the original equation (2xy=-4) and rearrange for x. x=-2/y. Producing x=-1 or x=8/3

AS
Answered by Amelia S. Maths tutor

3429 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Given that x : y = 7 : 4 and x + y = 88, calculate x - y.


Find a quarter of the area of a circle with a diameter of 10cm.


What is the solution to x^2 + 5x - 7 = 0


There are 10 boys and 20 girls in a class. The class has a test. The mean mark for all the class is 60. The mean mark for the girls is 54. Work out the mean mark for the boys


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