Question

Consider the function f(x) =x^2 +2x -15 For what values of x does the function equal 0

Answer 1

Answer:

x = -5

x = 3

Explanation:

The given function is:

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

If the function equals zero, set f(x) = 0 and solve for x

$\begin{gathered} 0=x^2+2x-15 \\ \\ x^2+2x-15=0 \\ \\ x^2-3x+5x-15=0 \\ \\ x(x-3)+5(x-3)=0 \\ \\ (x-3)(x+5)=0 \\ \\ x-3=0 \\ x=3 \\ \\ x+5=0 \\ x=-5 \end{gathered}$

The function equals zero at x = -5 and x = 3

x = -5

x = 3