How do I factorise quadratic equations?

To factorise an expression such as x 2 - 8x + 15, you need to look for two numbers that add up to make -8 and multiply to give 15.
The only option in this case is -5 and -3
(-5)+(-3)=-8and (-5)x(-3)=15as two negative numbers multiply to a positive number.

MG

Related Maths GCSE answers

All answers ▸

Work out the value of 27 ^-2/3


write 36 as a product of its prime factors


John ran a race at his school. The course was measured at 450m correct to 2sf and his time was given at 62 econds to the nearest second. Calculate the difference between his maximum and minimum possible average speed. Round you answer to 3sf.


Solve the simultaneous equations: 2x + y = 5 , x + 4y = -22