x - 2y = 1 , x^2 + y^2 = 13 find the solutions to this quadratic equation

equation 1) x - 2y = 1equation 2) x2 + y2 = 13
Rearrange equation 1 to: x = 1+2ysubstitute into equation 2: (1+2y)2 + y2=13expand first bracket: (1+2y)(1+2y) +y2 =13(1+4y+4y2) +y2 = 13Collect like terms: 5y2+4y-12=0Factorise by recognition: (5y-6)(y+2)=0solve each bracket: y= 6/5 or y=-2Rearrange equation 1: x= 1+2ySubstitute y values into equation 1: x= 1+ 2(6/5) = 17/5x= 1+2(-2)= -3


CS
Answered by Caitlin S. Maths tutor

3070 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Test


Show that (x + 1)(x + 2)(x + 3) can be written in the form ax3 + bx2 + cx + d where a, b, c and d are positive integers.


Solve the simultaneous equations 'x-2y=3' and 'x^2+2y^2=27'


Please expand the following brackets: (x+3)(x+5). Give your answer in its simplest form.


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:

© 2025 by IXL Learning