19.1k views
5 votes
The equation f(x) = 5x2 − 30x + 6 represents a parabola. What is the vertex of the parabola?

(−5, 281)
(5, −19)
(−3, 141)
(3, −39)

User AndrewJE
by
7.9k points

2 Answers

6 votes
The answer is D. (3,-39)

Just plug the numbers into the formula to find the Parabola.

f(x) = ax
x^(2)+ bx + c

Then find X:

x = -

(b)/(2a)
Then solve.


Hope this helped. Have a great day!
User INSANENEIVIESIS
by
8.4k points
2 votes

Answer:

D.
(3,-39)

Explanation:

We have been given an equation
f(x)=5x^2-30x+6. We are asked to find the vertex of parabola for our given equation.

We will use formula
x=(-b)/(2a) to find the x-coordinate of the vertex of parabola, then we will substitute the value of x-coordinate in our equation to find the y-coordinate of the parabola.


x=(-(-30))/(2*5)


x=(30)/(10)


x=3

Therefore, the x-coordinate of the vertex of the parabola is 3.

Now let us substitute
x=3 in our given equation to find the y-coordinate of the parabola.


f(3)=5(3)^2-30(3)+6


f(3)=5*9-90+6


f(3)=45-90+6


f(3)=51-90


f(3)=-39

So, the y-coordinate of the vertex of parabola is
-39. The point
(3,-39) represents the vertex of the parabola represented by our given equation and option D is the correct choice.