Solve the quadratic equation x^2+5x+6=0

There are two approaches which can be taken when solving this equation. The first is using the quadratic equation. By comparing the coefficients of the example to the general quadratic equation, a(x^2)+b(x)+c=0, we can set a=1, b=5 and c=6. We will now use the quadratic formula,x=(-b±√(b^2-4ac))/2a, and the values of a, b and c. Therefore, x==(-5±√(5^2-4x1x6))/2x1 We get that x=3 or x=2. The second approach is to use trial and error to find a pair of numbers which sum to 5 and whose product is 6, let us call these numbers d and e. Therefore, we need to find d and e such that b=d+e=5 and c=de=6. If these are satisfied, x=d or x=e. After trialling the possible pairs, 3 and 2 are a suitable pair, hence x=3 or x=2.

Answered by Anna M. Maths tutor

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