Question

Factor the quadratic expression in the equation y=2x^2+28x+96 and use the factors to find the zeros of the equation. Then, use the zeros to find the line of symmetry of the parabola represented by the equation.
What is the equation for the line of symmetry of the parabola represented by the equation y=2x^2+28x+96?


Enter your answer as the correct equation, like this: x = 42

Answer 1

Answer:

$x=-7$

Step-by-step explanation:

We have been given an equation $y=2x^2+28x+96$. We are asked to find the zeros of equation by factoring and then find the line of symmetry of the parabola.

Let us factor our given equation as:

$2x^2+28x+96=0$

Dividing both sides by 2:

$x^2+14x+48=0$

Splitting the middle term:

$x^2+6x+8x+48=0$

$(x^2+6x)+(8x+48)=0$

$x(x+6)+8(x+6)=0$

$(x+8)(x+6)=0$

Using zero product property:

$(x+8)=0\text{ (or) }(x+6)=0$

$x+8=0\text{ (or) }x+6=0$

$x=-8\text{ (or) }x=-6$

Therefore, the zeros of the given equation are $x=-8\text{ (or) }x=-6$.

We know that the line of symmetry of a parabola is equal to the x-coordinate of vertex of parabola.

We also know that x-coordinate of vertex of parabola is equal to the average of zeros. So x-coordinate of vertex of parabola would be:

$\frac{-8+(-6)}{2}=\frac{-14}{2}=-7$

Therefore, the equation $x=-7$ represents the line of symmetry of the given parabola.