Answer:
We calculate the slop of a line.
How to find the slope:
Pick any two points on a graph
The formula of slope is 
For example we have two points that contains the coordinates (5,2) (7,4)
Inserting them to the formula would result in:

=
Our rate of change is rise 2, run 2.
Answer:

Step-by-step explanation:
Given that,
The dimensions of a rectangular block = 4 cm x 2 cm x 1.5 cm
Mass, m = 93.6 g
We need to find the density of steel. We know that the density of an object is equal to the mass divided by volume. So,

So, the density of the steel is
.
From the table we can see:
Number of songs: Cost:
0 $ 0
1 $1.25
2 $2.50
3 $3.75
4 $5.00
Therefore the rate of change is: (2.50 - 1.25) / ( 2 - 1 ) = $1.25
Answer:
It means that : C. The cost increases $1.25 for each additional song that is downloaded.
a=1 b= c=Step-by-step explanation:
Think about this. What do the numbers in a coordinate stand for? They stand for X and Y. If you're trying to figure out what the X is, wouldn't you be solving for x? And didn't they just give you an equation? ;) First off, do you see how the "Y" value is given to you in the coordinate? All you have to do is substitute that 3 in for the "y" in the equation! 3=2x+5. Hey.... that looks like a simple equation! First, you need to subtract 5 from the other side of the equation. Now you're left with 2x=-2. Divide both sides by 2, and you get that x=-1. Now, just substitute that "x' value into the coordinate, and your answer should come out to be (-1, 3). :D