Solve the simultaneous equations. x^2 + 2y=9, y-x=3

Use the method of substitution to answer this question.
Step 1: Rearrange one of the equations to find x or y.
y-x=3 y=x+3
Step 2: Substitute your y into the first equation
x2+2y=9 x2+2(x+3)=9
Step 3: Expand the brackets and rearrange to form a quadratic equation
x2+2x+6=9 x2+2x-3=0
Step 4: Factorise the equation to find your values for x
(x+3)(x-1)=0Therefore x=-3 or x=1
Step 5: Find the corresponding y values
y=x+3when x=-3 y=0 and when x=1 y=4

KW
Answered by Kieran W. Maths tutor

4373 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve simultaneously: 2x + y = 18 and x - y = 6


What is mathematics and why should I study it?


A shop sells only Apples, Bananas and Mangos. The ratio of Apples to Bananas is 5:11. The next shopper will choose one piece of fruit at random. The probability that they buy a Mango is 0.2. What is the probability that they buy an Apple?


The diagram shows the position of two ships, A and B, and a lighthouse L. Ship A is 5km from L on a bearing of 070° from L. Ship B is 3km from L on a bearing of 210° from L. Find the distance between A and B correct to 3.s.f.


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