How to solve a quadratic equation without a calculator?

You factorise it. First, you find a common factor between a, b and c. Then, you find the 2 numbers that multiplied give you c and added give you b. If a=1, then the additive inverse of those 2 numbers are the answers. If a does not equal 1, you decompose b into the 2 numbers that multiplied give you c and added give you b. You find common factors and then you will find the answers.

JP

Related Maths GCSE answers

All answers ▸

How can I find the size of an angle in a right-angled triangle if I know the lengths of two of the sides?


You have a list of numbers: 1, 45, 81, 40, 7, 8, 14, 23, 7, 4. Calculate the mode, median, and mean.


Fully simplify the expression: 4 / (sqrt(8) + 4)


A common question would be how to factorise into two brackets, for example x^2 + 5x = -6