Solve the simultaneous equations : x ^2+2y=9, y=x+3 to find solutions for x and y.

We must use the substitution method for this question because the first equation is a quadratic. Take the more simple equation (the second one), and use that to substitute the value for y in to the first equation:x^2+2(x+3)=9. Expand the brackets and rearrange to get: x^2+2x-3=0.Now we must factorise, which will give us 2 solutions for x. Factorising gives: (x+3)(x-1)=0.The solutions for x are therefore, x = -3, x = 1. Using these solutions for x and substituting them on to the other equation will give us corresponding solutions for y:When x = -3, y = 0 and when x = 1, y = 4.

CR
Answered by Callum R. Maths tutor

3328 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

(b) In 2013, the price for each unit of electricity was 13.5 cents. Over the next 3 years, this price increased exponentially at a rate of 8% per year. Calculate the price for each unit of electricity after 3 years


Find an equation of the line which passes through the point (4,-7) and has slope 3.


A rectangle has a shorter side with a length of x and a longer side with a length of x + 8, the perimeter of the rectangle is 80cm. Calculate the value of x.


What is a surd? How would you go by simplifying a surd?


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