Answer:
Step-by-step explanation:
we know that
The equation of a vertical parabola into vertex form is equal to
where
(h,k) is the vertex of the parabola
if a> 0 then the parabola open upward (vertex is a minimum)
if a< 0 then the parabola open downward (vertex is a maximum)
In this problem we have
Convert to vertex form
Complete the square
--------> equation in vertex form
The vertex is the point 
the parabola open upward (vertex is a minimum)
The discount price will be 0.8X dollars.
Step-by-step explanation:
Given,
Price of an item = X dollars
Discount = 20%
Amount of discount = 20% of Price of item
Amount of discount =
Price of item after discount = Price of item - Amount of discount
Price of item after discount = X-0.2X = 0.8X dollars
The discount price will be 0.8X dollars.
Keywords: discount, subtraction
The answer is <span>B. y = x^3 + 4x^2 + 2x - 2
A line that passes through all given point is the correct choice. Now, substitute x and y in all of the choices:
</span>B. y = x³ + 4x²<span> + 2x - 2
Point 1: </span><span>(-2, 2)
x = -2
y = 2
____
2 = (-2)</span>³ + 4 *(-2)² + 2 * (-2) - 2
2 = -8 + 4 * 4 + (-4) - 2
2 = -8 + 16 - 4 - 2
2 = 2
_____
Point 2: (-1, -1)
x = -1
y = -1
____
-1 = (-1)³ + 4 *(-1)² + 2 * (-1) - 2
-1 = -1 + 4 * 1 + (-2) - 2
-1 = -1 + 4 - 2 - 2
-1 = -1
____
Point 3: (1, 5)
x = 1
y = 5
____
5 = (1)³ + 4 *(1)² + 2 * 1 - 2
5 = 1 + 4 * 1 + 2 - 2
5 = 1 + 4 + 2 - 2
5 = 5
____
Point 4: (3, 67)
x = 3
y = 67
____
67 = (3)³ + 4 *(3)² + 2 * (3) - 2
67 = 27 + 4 * 9 + 6 - 2
67 = 27 + 36 + 6 - 2
67 = 67
So, line B passes through all choices.
