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Using the given quadratic function f(x)=x^2+2x-15, find the following information

User Charles Burns
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1 Answer

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we have a quadratic function

f(x) = x^2 + 2x - 15

let f(x) = y

then, y = x^2 + 2x - 15

let y = 0

x^2 + 2x - 15 = 0

Using factorization method

the factors of -15 are as follows

-1 and 15, -3 and 5, 3 and -5, 1 and -15

the only factor when we multiply that we give us -15 and when we add that will give us 2 are -3 and 5

x^2 + 5x - 3x - 15

x^2 + 5x - 3x - 15 = 0

grouping the expression

we have

x(x + 5) - 3(x + 5) = 0

(x+5) =0 or (x-3)=0

x+5 = 0 or x-3 = 0

x = 0 - 5 or x = 0 + 3

x = -5 or x = 3

x can either be -5 and 3

therefore, the maximum value is 3 and the minimum value is -5

User Lanaru
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