How do you solve a quadratic equation? eg: x^2 + 2x - 8

Well, when solving quadratic equations we have two options, either A: factorize the equation and solve or B: Use the '-b' formula. Option A is usually a lot quicker but does require you to practice factorizing in order to utilize it fully, whereas option B is consistent and requires less thinking as it simply consists of plugging equations into a formula. For this example, x2 +2x-8, factorizing is the better option. For a quadratic factorization, there are two factors that need to sum to the middle term and their product must equal the final term. In this case, the factors of -8 that sum to 2 which are x=-2 and x=4. This leaves us with (x-2)(x+4), this means that our answers for the quadratic equation are +2 and -4.

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Answered by Ahad K. Maths tutor

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