Answer:
c = 1.29s + 2
Step-by-step explanation:
c represents the total cost
s represents the number of songs downloaded
1.29 represents the cost charged for every song downloaded
2 represents the initial cost to download the app
something noteworthy is that the independent and squared variable in this case will be the "x", namely the graph of that quadratic is a vertical parabola.
![\bf f(x) = (x+2)(x-4)\implies 0=(x+2)(x-4)\implies x = \begin{cases} -2\\ 4 \end{cases} \\\\\\ \boxed{-2}\rule[0.35em]{7em}{0.25pt}0\rule[0.35em]{3em}{0.25pt}\stackrel{\downarrow }{1}\rule[0.35em]{10em}{0.25pt}\boxed{4}](https://tex.z-dn.net/?f=%5Cbf%20f%28x%29%20%3D%20%28x%2B2%29%28x-4%29%5Cimplies%200%3D%28x%2B2%29%28x-4%29%5Cimplies%20x%20%3D%20%5Cbegin%7Bcases%7D%20-2%5C%5C%204%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%20%5Cboxed%7B-2%7D%5Crule%5B0.35em%5D%7B7em%7D%7B0.25pt%7D0%5Crule%5B0.35em%5D%7B3em%7D%7B0.25pt%7D%5Cstackrel%7B%5Cdownarrow%20%7D%7B1%7D%5Crule%5B0.35em%5D%7B10em%7D%7B0.25pt%7D%5Cboxed%7B4%7D)
so the parabola has solutions at x = -2 and x = 4, and its vertex will be half-way between those two guys, namely at x = 1.
since this is a vertical parabola, its axis of symmetry, the line that splits its into twin sides, will be a vertical line, and it'll be the x-coordinate of the vertex, since the vertex hasa a coordinate of x = 1, then the axis of symmetry is the vertical line of x = 1.
Answer:
Graph A
Step-by-step explanation:
The graph of a proportional relationship is a straight line through the origin. Only graph A goes through the origin.
Discounted Cost= Cost of Item - (Cost of Item * % Discount)
= $45.60 - ($45.60 * 30%)
convert % to decimal (30% ÷ 100)
= 45.60 - (45.60 * 0.30)
multiply in parentheses
= 45.60 - 13.68
= $31.92 discounted cost
ANSWER: The discounted cost of the item is $31.92 (savings of $13.68).
Hope this helps! :)