Answer:
y = -2x^2 -4x +5
Step-by-step explanation:
The vertex is at (-1,7) and the y intercept is at (0,5)
The vertex form of a parabola is
y = a(x-h)^2 +k
where (h,k) is the vertex
y = a(x--1)^2 +7
Then substitute the point into the equation
y = a(x+1)^2 +7
5 = a(0+1)^2 +7 +7
Subtract 7 from each side
5-7 = a(1)^2
-2 = a
y = -2(x+1)^2 +7
Now FOIL
y = -2 (x^2 +2x+1) +7
Then distribute
y = -2x^2 -4x-2 +7
y = -2(x + 1)² + 7
y = -2x² - 4x + 5
Vertex: (-1,7)
y = a(x - -1)² + 7
y = a(x + 1)² + 7
Find a using (1,-1)
-1 = a(1 + 1)² + 7
-8 = 4a
a = -2
y = -2(x² + 2x + 1) + 7
y = -2x² - 4x - 2 + 7
D. (2.5;-0.75)
the coordinates of the given point P can be:
(2.5;-0.75) or (-2.5; 1.75).
Among the suggested answers the correct one is D only.
