f(x)=x^2+12x+32=0, solve for x

Method 1: Quadratic formulaf(x)= ax2+bx+c, therefore a=1, b=12, c=32 - quadratic formula= (-b+/-(b2-4ac)1/2)/2ax=(-12+(144-128)1/2/2 = -4 or x=(-12-(144-128)1/2)/2 = -8
Method 2: FactoriseWe need to find a pair of numbers that when added make 12 and when multiplied make 32, 8 and 4 are our numbersTherefore f(x) can be written as (x+8)(x+4)The solutions to x are the numbers that make either bracket equal to 0, therefore x=-8 or x=-4

Answered by Maths tutor

3201 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

There are 892 litres of oil in Mr Aston’s oil tank. He uses 18.7 litres of oil each day. Estimate the number of days it will take him to use all the oil in the tank.


write log2(5) +log2​​​​​​​(3) in its simplest form


If a rectangle has length (x-4), width (x-5) and area 12 then what is the value of x?


Bob and Bill have 50 sweets to share in the ratio 4:6 respectively. how many do they each get?


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