Solve the simultaneous equations x^2 + y^2 = 9 and y = 3x + 3

y2 = (3x + 3)2 = 9x2 + 18x + 9

x2 + 9x2 + 18x + 9 = 9

10x2 + 18x = 0 (root a: x = 0)

5x + 9 = 0 (root b: x = -1.8)

For x = 0, y = 3(0) + 3 (root a: y = 3)

For x = -1.8, y = 3(-1.8) + 3 (root b: y = -2.4)

Solutions at (0, 3) and (-1.8, -2.4)

AR
Answered by Alistair R. Maths tutor

3780 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

factorise and simplify (x^2+4x+4)/(3x^2+15x+18)


a) You area told that y is proportional to x2 and that when y = 75, x = 5. Find a formula for y in terms of x. y = x b) Find the value of y when x = 3. c) Find the value of x when y = 1200.


Expand and simplify (x – 9)(x + 2)


PQRS is a parallelogram with P->Q=a and P->S=b. Find S->Q in terms of a and b. N is a point between S and Q, where SN:NQ is 3:2, find N->R


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences