Answer:
121.92 cm cubed
Step-by-step explanation:
all you have to do is multiply all 3 measurements to find the simple shapes volume, and then convert to centimeters using the simple 2.54 cm=1 in conversion rate
Substitution or elimination
First the equation needs to be set to "y" to find the total amount of miles traveled:
y=
Then you know he has already gone 3.5, this is a constant and can be added to the graph immediately
y=3.5
Then you know every two hours he can cover 100 miles, which means 50 miles per hour or 50 per x, so add 50x to 3.5 to show that he will go 3.5 miles plus 50 miles for every hour he is traveling.
y=3.5+50x
Answer: 
This is the same as writing y < (-1/2)x+3
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Explanation:
The dashed boundary line goes through (0,3) and (4,1)
Apply the slope formula for those two points
m = (y2-y1)/(x2-x1)
m = (1-3)/(4-0)
m = -2/4
m = -1/2
The slope of the dashed line is -1/2. The y intercept is 3. So we go from y = mx+b to y = (-1/2)x+3 to represent the equation of the dashed line. This is the same as writing 
We shade below the dashed line to represent the inequality
. Points in the shaded region are solutions to the inequality. One example point is (0,0).
Note that we don't have "or equal to" as part of the inequality sign because we are not including points on the boundary. A solid line, rather than a dashed line, would include points on the boundary.