D is a function because there are no repeated x values
for example b is not a function because we have (0,-7) and (0,-9)
Answer:
I do
Step-by-step explanation:
The vertex form of a quadratic function is:
f(x) = a(x - h)² + k
The coordinate (h, k) represents a parabola's vertex.
In order to convert a quadratic function in standard form to the vertex form, we can complete the square.
y = 2x² - 5x + 13
Move the constant, 13, to the other side of the equation by subtracting it from both sides of the equation.
y - 13 = 2x² - 5x
Factor out 2 on the right side of the equation.
y - 13 = 2(x² - 2.5x)
Add (b/2)² to both sides of the equation, but remember that since we factored 2 out on the right side of the equation we have to multiply (b/2)² by 2 again on the left side.
y - 13 + 2(2.5/2)² = 2(x² - 2.5x + (2.5/2)²)
y - 13 + 3.125 = 2(x² - 2.5x + 1.5625)
Add the constants on the left and factor the expression on the right to a perfect square.
y - 9.875 = 2(x - 1.25)²
Now, we need y to be by itself again so add 9.875 back to both sides of the equation to move it back to the right side.
y = 2(x - 1.25)² + 9.875
Vertex: (1.25, 9.875)
Solution: y = 2(x - 1.25)² + 9.875
Or if you prefer fractions
y = 2(x - 5/4)² + 79/8
Based on the given problem above, here is the solution.
Given: Iris's charge: 470
1 1/5 times her fee: additional hourly rate
? = fee for an hourly rate
What we need to do first is divide 470 by 7 hours, so 470/7 = 67.143/hour.
So Iris's per hour is 67.143 without the additional rate.
Now, let's look for the 1 1/5 of 470. 1 1/5 is equal to 1.2. So 470 x 1.2 = 564.
To get the total fee of her hourly rate, we add 67.143 and 564, so Iris's hourly rate then is 631.143 or 631.14.
40 miles an hour and yeah..
