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Please help asap I genuinely cannot figure this out

Find the equation of the parabola that has zeros of x = –2 and x = 3 and a y–intercept of (0,–30).


A) y = 5x2+ 5x – 30

B) y = –5x2 + 5x + 30

C) y = 5x2 – 5x – 30

D) y = x2 – 5x – 30

User YKa
by
3.4k points

2 Answers

3 votes

Answer:

5,x6=5

4÷6=6

4=6=8

4=6687554=+÷976555££=6££6/=

User Brent Dillingham
by
3.6k points
6 votes

Answer:

C

Explanation:

We can use the factored form of the quadratic equation, given by:


y=a(x-p)(x-q)

Where a is the leading coefficient and p and q are the zeros.

We have zeros x = -2 and x = 3. So, let p = -2 and q = 3:


y=a(x+2)(x-3)

Next, we are given that our y-intercept is (0, -30).

In other words, when x = 0, y = -30. So:


-30=a(0+2)(0-3)

Solve for a:


-30=-6a\Rightarrow a=5

Hence, our factored equation is:


\displaystyle y=5(x+2)(x-3)

For the standard form, expand:


y=5(x^2-3x+2x-6)

Simplify:


y=5(x^2-x-6)

Distribute:


y=5x^2-5x-30

Our answer is C.

User Mpjdem
by
4.4k points