Solve x^2 = 4(x - 3)^2

First multiply out the bracket.x^2 = 4(x - 3)^2 then becomes x^2 = 4(x^2 - 6x + 9)Expand the right hand side further. x^2 = 4x^2 - 24x + 36Collect like terms. 3x^2 - 24x + 36 = 0The number 3 is a common factor of each coefficient. Divide through by 3.x^2 - 8x + 12 = 0Factorise the equation by looking for two numbers that multiply to create 12 and add to create -8. Consider the factorisation of 12 to find these numbers.Common Factors of 12: (1,12), (2,6), (3,4), (-1,-12), (-2,-6), (-3,-4)-2 x -6 = 12 and -2 + -6 = -8Therefore the equation can be factorised:(x - 2)(x - 6) = 0Either (x - 2) or (x - 6) must be equal to zero. Solve for x by setting each one equal to 0.Therefore, x = 2, 6.

JB
Answered by Jenny B. Maths tutor

2677 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations: 4x + y = 25, x - 3y = 16


What is the point of intersection of two lines, and how would I find it?


Re-arrange [4x+ 9t + 8s= 3g] to make x the subject of the formula


n is an integer such that 3n + 2 ≤ 14, and 6n/(n^2 + 5) >1. Find all possible values of n.


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