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Is this quadratic? If so what form is it?

Is this quadratic? If so what form is it?-example-1
User Fredrivett
by
4.5k points

2 Answers

4 votes

Answer:

Yes. Factored form.

Explanation:

User Alexander Vasenin
by
5.3k points
3 votes

Answer:

yes, and it's in intercept form

Explanation:

Hi there!

We are given the function f(x)=-2(x-4)(x+3)

A quadratic function is a function that has a degree of 2 (the highest exponent in the function is to the 2nd power)

There are 3 forms to write a quadratic function:

standard form, which is f(x)=ax²+bx+c, where a, b, and c are free coefficients (numbers)

vertex form, which is f(x)=a(x-h)²+k, where a is a free coefficient and (h,k) is the vertex

intercept form, which is f(x)=a(x-
x_(1))(x-
x_(2)), where a is a free coefficient and
x_(1) and
x_(2) are the x intercepts

You may notice that f(x)=-2(x-4)(x+3) is actually in intercept form; a is -2 and
x_(1) and
x_(2) are 4 and -3 respectively (remember: the formula for intercept form has -
x_(1) and -
x_(2), but the x intercepts are
x_(1) and
x_(2). Therefore, the x intercepts should be the opposites of -
x_(1) and -
x_(2)).

If the formula is in intercept form, it should be quadratic.

However, if you want to be sure it's quadratic, you can expand the function.

f(x)=-2(x-4)(x+3)

first, multiply the binomials together using FOIL

(x-4)(x+3)

x²-x-12

now multiply x²-x-12 by -2

-2(x²-x-12)

do the distributive property

-2x²+2x+24

It's a quadratic function! The value of the highest exponent is 2 :)

Hope this helps!

User Rameez SOOMRO
by
5.3k points