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

2972 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve algebraically: 6a+b=16, 5a-2b=19


I feel really nervous about time pressure in the exam, I don't think I'll finish


Help! How do I solve quadratic equations?


Solve the simultaneous equations: 5x+5y = 6 7x+3y = 6


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