How do you use the quadratic formula?

So we use the quadratic formula to find out 2 values of x satisfies the quadratic equation we have been given. First we need to write the quadratic formular down, (x=-b.. etc). If you see, we need to plug in 3 different numbers corrosponding to a, b and c into the formula to find what x is. A, b and c can be found by looking at the numbers in front of the x terms in our quadratic equation. 'A' is the number found before the x2 term, 'b' before the x term and c is the final number which isnt linked to one of the x terms. If you insert these numbers into the quadratic formula, once adding the square root and once minusing it, you will get the 2 values of x you have been looking for. 

Answered by Amy B. Maths tutor

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