Solve the simultaneous equations x^2+ y^2 = 29 and y–x = 3

For this question we will be using the substitution method in order to solve this question. Firstly we will take the less complex equation and rearrange to make either x or y the subject of the formula. We will make y the subject of the formula in this case. So y-x = 3 becomes y = x+3. We will now substitute this equation for y into our other equation. So x^2+y^2 = 29 will now become x^2+(x+3)^2 = 29. Next we will expand and simplify this equation. x^2+(x+3)^2 = 29 now becomes x^2+3x-10=0. This is a quadratic equation, this can be solved using the quadratic formula giving answers of x = -5 and x = 2. These two values for x can now be substituted back into the eqaution y-x = 3 to give y = -2 (for x = -5) and y = 5 (for x=2). These are the solutions to the equation.

RC
Answered by Rio C. Maths tutor

4233 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

The perimeter of a right-angled triangle is 81 cm. The lengths of its sides are in the ratio 2 : 3 : 4. Work out the area of the triangle.


Expand the brackets (2x + 3)(3x - 1)


How do I find the equation of a line connecting points a(p,q) and b(r,s)?


How do you factorise a quadratic with a co-efficient in front of the x^2 - e.g: 3x^2 + 14x + 8


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