Question

Question #2Several points are plotted on the graph. Which of the plotted points on the graph represent the zeros of the function:f (x) = (x^2+ 2x- 8) (x – 6)

Answer 1

Given function is:

`f(x)=(x^2+2x-8)(x-6)`

Now put f(x)=0

`\begin{gathered} (x^2+2x-8)(x-6)=0 \\ (x^2+2x-8)=0,(x-6)=0 \\ x-6=0 \\ x=6 \end{gathered}`

so the first point is (6,0) now for another points:

`\begin{gathered} (x^2+2x-8)=0 \\ (x^2+4x-2x-8)=0 \\ x(x+4)-2(x+4)=0 \\ (x+4)(x-2)=0 \\ x=-4,2 \end{gathered}`

So the points are (-4,0) and (2,0) and(6,0)

Hence the correct options are 1,2 and 4.