Given that the directrix is at y = 4 and the focus is at (0, -4), then the vertex is at (h, k) = (0, 0).
p is the distance between the vertex and the focus and between the vertex and the directrix = 4 and since the focus is below the directrix, p is negative, i.e. p = -4
Equation of a parabola is given by (x - h)^2 = 4p(y - k)
Therefore, the required equation is (x - 0)^2 = 4(-4)(y - 0)
x^2 = -16y
y = -1/16 x^2
She spent $310 on the singing camp.
MY WORK:
I multiplied $86.50*20 because $86.50 is the amount she deposited for 20 months. $86.50*20=$1740.00
Then I multiplied $24.50*20 because she spent $24.50 for 20 months. $24.50*20= $490.00
Then I subtracted $1740.00-$490.00 because she spent $490 out of her bank account. $1740.00-$490.00=$1240.00
Finally, because its 1/4 of her money, I divided $1240.00 by 4. $1240 divided by 4= $310
Hope this helps!!
:)
Answer:

General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
- Slope Formula:

Step-by-step explanation:
<u>Step 1: Define</u>
<em>Find points from graph.</em>
Point (1, -5)
Point (7, -1)
<u>Step 2: Find slope </u><em><u>m</u></em>
Simply plug in the 2 coordinates into the slope formula to find slope <em>m</em>
- Substitute [SF]:

- Add/Subtract:

- Simplify:
