Discover new information and insights with the help of IDNLearn.com. Whether your question is simple or complex, our community is here to provide detailed and trustworthy answers quickly and effectively.

What is the equation of the quadratic function with a vertex at (2,–25) and an x-intercept at (7,0)? f(x) = (x – 2)(x – 7) f(x) = (x 2)(x 7) f(x) = (x – 3)(x 7) f(x) = (x 3)(x – 7)

Sagot :

The quadratic equation with the given characteristics is:

f(x) = (x + 3)*(x - 7).

How to get the quadratic equation?

We know that the vertex must be (2, -25) and it passes through (7, 0).

For a quadratic equation:

y = a*x^2 + b*x +c

The x-value of the vertex is:

x = -b/2a

Then we have:

2 = -b/2a

We also have:

-25 = a*4 + b*2 + c

And because the function passes through (7, 0) we know that 7 is one of the roots, then:

0 = a*49 + b*7 + c

Then we have 3 equations to work with:

2 = -b/2a

-25 = a*4 + b*2 + c

0 = a*49 + b*7 + c

If we subtract the third and second equations we get:

25 = a*45 + b*5

Now, with the first equation we can rewrite:

a  = -b/4

Replacing that in the other equation:

25 = a*45 + b*5

25 = (-b/4)*45 + b*5 = b*(-25/4)

25*(-4/25) =b = -4

Now we know the value of b.

2 = -(-4)/2a

a = 1

Now we need to find the value of c, we have that:

0 = 1*49 + -4*7 + c

0 = 49 - 28 + c

0 = 21 + c

Then c = -21

The equation is:

[tex]y = x^2 - 4x - 21[/tex]

It can be factorized to:

f(x) = (x + 3)*(x - 7).

If you want to learn more about quadratic equations:

https://brainly.com/question/1214333

#SPJ4