How do I solve a quadratic equation?

In a quadratic equation the highest power is 2. This means that we are looking for up to 2 answers. The first thing we are going to try to do is factorise the equation. We draw two sets of brackets side by side. In each bracket, we will have x +/- some number. We need to work out what those numbers should be. (Shows example equation) In this example the number next to the x term is 5 and the number out here on its own is 6. We need to find two numbers which multiply to together to make 6 and also add together to make 5. Can you think of any? (Once answer is found or given) So now we write x+2 in the first bracket and x+3 in the second bracket. See how this whole equation is equal to 0? That means that the answers to the equation have to be something + 2 = 0 and something + 3 = 0. So what would the two answers be?(Once answer is found or given) To check that you are right replace the Xs with each answer to see if you get zero.

LW

Related Maths GCSE answers

All answers ▸

Write (x + 1)(x + 2)(x + 3) in the form ax³ + bx² + cx + d


3x + 2y = 6, 5x+3y=11, solve for x and y.


Before an exam, I always go through as many past papers as possible but I still don't know how to do the questions on an exam when they come up, why and what can I do?


There are 5 blue counters and 5 red. x takes 2 counters out of the bag without replacing them. What is the probability x took 2 red counters.