The answer would be 81.2 because all you gotta do it 20.3 times 4
The distance from city C to city D is 4,814 miles.
<h3>3
Answers:</h3>
A) y intercept is (0,3)
C) Axis of symmetry is x = -1
D) Vertex is (-1, 4)
So basically everything but choice B is true.
========================================
Explanation:
Choice A is true because plugging in x = 0 leads to y = 3. Effectively, anything with an x goes away when x = 0 leaving that 3 behind. So finding the y intercept in this form is fairly fast.
-------------------
To check choices B through D, let's convert the equation into vertex form.
y = -1x^2 - 2x + 3 is in the form y = ax^2 + bx + c where
a = -1
b = -2
c = 3
The vertex is located at (h,k) such that h = -b/(2a)
Plug the values of 'a' and 'b' into the equation below
h = -b/(2a)
h = -(-2)/(2*(-1))
h = 2/(-2)
h = -1
The x coordinate of the vertex is x = -1
Then use this to find the y coordinate of the vertex
y = -1x^2 - 2x + 3
y = -1(-1)^2 - 2(-1) + 3
y = 4
The y coordinate of the vertex is 4, meaning k = 4
The vertex overall is (h,k) = (-1, 4)
This shows choice D is true, meaning choice B has to be false.
Choice C is true because the axis of symmetry is the x coordinate of the vertex. This is the vertical line that cuts the parabola into two mirrored halves. This vertical line always goes through the vertex.
x = amount invested at 3%
y = amount invested at 12%
we know the total amount invested was 25,500 thus x + y = 25,500.
hmmm how much is 3% of "x"? well (3/100) * x or 0.03x.
how much is 12% of "y"? hmmmm (12/100) * y or 0.12y.
we know after a year the total interest was 2,250, therefore whatever "x" and "y" may be 0.03x + 0.12y = 2,250.
![\begin{cases} x + y &= 25500\\ 0.03x + 0.12y &= 2250 \end{cases}\qquad x + y = 25500\implies y = 25500-x \\\\\\ \stackrel{\textit{substituting in the 2nd equation}}{0.03x+0.12(25500-x)=2250}\implies 0.03x+3060-0.12x=2250 \\\\\\ -0.09x+3060=2250\implies -0.09x=-810\implies x=\cfrac{-810}{-0.09}\implies \boxed{x=9000} \\\\\\ \stackrel{\textit{we know that}}{y = 25500-x}\implies y = 25500 - 9000\implies \boxed{y = 16500}](https://tex.z-dn.net/?f=%5Cbegin%7Bcases%7D%20x%20%2B%20y%20%26%3D%2025500%5C%5C%200.03x%20%2B%200.12y%20%26%3D%202250%20%5Cend%7Bcases%7D%5Cqquad%20x%20%2B%20y%20%3D%2025500%5Cimplies%20y%20%3D%2025500-x%20%5C%5C%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bsubstituting%20in%20the%202nd%20equation%7D%7D%7B0.03x%2B0.12%2825500-x%29%3D2250%7D%5Cimplies%200.03x%2B3060-0.12x%3D2250%20%5C%5C%5C%5C%5C%5C%20-0.09x%2B3060%3D2250%5Cimplies%20-0.09x%3D-810%5Cimplies%20x%3D%5Ccfrac%7B-810%7D%7B-0.09%7D%5Cimplies%20%5Cboxed%7Bx%3D9000%7D%20%5C%5C%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bwe%20know%20that%7D%7D%7By%20%3D%2025500-x%7D%5Cimplies%20y%20%3D%2025500%20-%209000%5Cimplies%20%5Cboxed%7By%20%3D%2016500%7D)
Answer: there
if you multiply 15 and 0.44 you get 6.60. so technically 0.44x15=6.60.