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Solve the following quadratic function by factoring f(x) = x2 – X – 12 Enter the number that belongs in the green box. x = 4; x = [?] Enter

Respuesta :

The given function is

[tex]f(x)=x^2-x-12[/tex]

To solve it by factoring, we have to look for two numbers whose product is 12 and whose difference is 1. Those numbers are 4 and 3.

[tex]f(x)=(x-4)(x+3)=0[/tex]

Then, we use the zero property

[tex]\begin{gathered} x-4=0\rightarrow x=4 \\ x+3=\rightarrow x=-3 \end{gathered}[/tex]

Hence, the answer is -3.