One form of the equation of a parabola is
y = ax² + bx + c
The curve passes through (0,-6), (-1,-12) and (3,0). Therefore
c = - 6 (1)
a - b + c = -12 (2)
9a + 3b + c = 0 (3)
Substitute (1) into (2) and into (3).
a - b -6 = -12
a - b = -6 (4)
9a + 3b - 6 = 0
9a + 3b = 6 (5)
Substitute a = b - 6 from (4) into (5).
9(b - 6) + 3b = 6
12b - 54 = 6
12b = 60
b = 5
a = b - 6 = -1
The equation is
y = -x² + 5x - 6
Let us use completing the square to write the equation in standard form for a parabola.
y = -[x² - 5x] - 6
= -[ (x - 2.5)² - 2.5²] - 6
= -(x - 2.5)² + 6.25 - 6
y = -(x - 2.5)² + 0.25
This is the standdard form of the equation for the parabola.
The vertex us at (2.5, 0.25).
The axis of symmetry is x = 2.5
Because the leading coefficient is -1 (negative), the curve opens downward.
The graph is shown below.
Answer: y = -(x - 2.5)² + 0.25
36/27=1.3
7x1.3=9.1
The actual length is 9.1meters
-2x + 8 = -4x + 1
- 1 -2x
7 = -6x
—
-6x
7/-6 or -7/6
The area of Philip and Laura's pool is 3x^2 - 13x - 10 square feet
<h3>Area of a rectangle</h3>
Givene the dimensiion of Philip and Laura's pool as:
Length = (x - 5)
Width = (3x + 2)
Given the area expressed as:
f(x) = (x - 5)(3x + 2)feet
Taking the product will give:
f(x) = 3x^2 + 2x -15x - 10
f(x) = 3x^2 - 13x - 10
Hence the area of Philip and Laura's pool is 3x^2 - 13x - 10 square feet
Learn more on area of rectangle here: brainly.com/question/25292087