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Write an equation for a parabola with​ x-intercepts (-2,0) and (3,0) which passes through the point (2,-20)

Write the equation :

User Tanasi
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1 Answer

4 votes

Answer:

Three equations I found with two variables:

1. -20 = a(2 - h)^2 + k

2. 0 = a(-2 - h)^2 + k

3. 0 = a(3 - h)^2 + k

Explanation:

To write the equation of a parabola with x-intercepts (-2,0) and (3,0) that passes through the point (2,-20), you can use the standard form of a quadratic equation:

y = a(x - h)^2 + k

In this equation:

- (h, k) is the vertex of the parabola.

- (x, y) is any point on the parabola.

- 'a' is a constant that determines the direction and width of the parabola.

Since the parabola has x-intercepts at (-2,0) and (3,0), we know that its roots are -2 and 3. This means that (x + 2) and (x - 3) are its factors. To find the equation, we can plug in the point (2,-20) to solve for 'a':

-20 = a(2 - h)^2 + k

Now, plug in the x-coordinate and y-coordinate of the given point (2,-20):

-20 = a(2 - h)^2 + k

-20 = a(2 - h)^2 - 20

Next, we use the x-intercepts to find h and k:

- When x = -2 (one x-intercept), y = 0, so:

0 = a(-2 - h)^2 + k

- When x = 3 (the other x-intercept), y = 0, so:

0 = a(3 - h)^2 + k

Now, we have a system of three equations with two variables (a, and h):

1. -20 = a(2 - h)^2 + k

2. 0 = a(-2 - h)^2 + k

3. 0 = a(3 - h)^2 + k

User MrBar
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