Find two solutions to the quadratic equation x^2 + 2x - 15 = 0
Firstly, we need to find two numbers that multiply together to make -15 and sum together to make +2. We try a few numbers and find that the solution is -3 and 5, as -3 x 5 = -15 and -3 + 5 = 2.Next you input these numbers into the brackets, like this: (x-3)(x+5)=0. This is the factorised equation.Now to find the two solutions, we let x-3 and x+5 equal 0. Therefore:x - 3 = 0 , x = 3 x + 5 = 0 , x = -5
JG
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