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eWhat are the zeros of the function f(x) = (2x+6)(x-4)?OA. x = 6 and x = -4OB. x=-6 and x = -4OC. x=3 and x = -4OD. x=-3 and x = 4

eWhat are the zeros of the function f(x) = (2x+6)(x-4)?OA. x = 6 and x = -4OB. x=-6 and-example-1
User Frederika
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1 Answer

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13 votes

Hello there. To solve this question, we have to remember some properties about roots of polynomials.

Given the following function:


f(x)=(2x+6)\cdot(x-4)

We want to determine its roots.

For this, we want to determine the values of x such that


f(x)=0

Then we have that


(2x+6)\cdot(x-4)=0

We know that a product of two values is equal to zero if and only if one of them is equal to zero.

So we have that


2x+6=0\text{ or }x-4=0

Subtract 6 on both sides of the first equation, we get


2x=-6

Divide both sides of the equation by a factor of 2


x=-3

Now for the second equation, add 4 on both sides of the equation


x=4

Hence we say that the roots of this function are


x=-3\text{ and }x=4

This is the answer contained in the last option.

User Josef Korbel
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