How do you solve a quadratic equation? I always forget how to do that!

x2+4x+3=0 The first step is to factorise. To do this you need to find a pair of factors of 3 that add together to make 4. I recommend listing the factors of 3 to start with. Don't forget the negatives! 1 and 3 (add to 4) -1 and -3 (add to -4) So now we have (x+1)(x+3)=0 The only way you can get 0 when you multiply two numbers together is if one of those numbers is 0. Therefore we set each of the brackets equal to 0 and solve. x+1=0 x=-1 x+3=0 x=-3

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Answered by Hannah D. Maths tutor

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