Solve the pair of simultaneous equations; (1) y + 4x + 1 = 0, (2) y^2 + 5x^2 + 2x = 0 .

Rearrage equation (1) to make y the subject of the formula. This gives y = -4x -1 .

Substitute this value of y into equation (2). This gives (-4x -1)^2 +5x^2 +2x = 0 . 

Expanding out the brackets gives 16x^2 + 8x + 1 + 5x^2 +2x =0 .

Collecting all the like terms gives 21x^2 +10x + 1 = 0 .

Factorising this equation gives (7x + 1)(3x + 1) = 0 which means x = -1/7, -1/3 . 

Substituting these x values back into (1) implies that y = - 3/7, 1/3 .

MG
Answered by Melanie G. Maths tutor

6501 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Given that y=π/6 at x=0 solve the differential equation,dy/dx=(e^x)cosec2ycosecy


Find the all the angles of a triangle with side lengths of 8cm, 11cm and 11cm.


differentiate 3x^56


Why does 1/x integrate to lnx?


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