Answer:
The expression is equal to 
Step-by-step explanation:
Let
x ----> the number of hours that the roller blades are rented
y ----> the cost of renting roller blades in dollars
we know that
The linear equation in slope intercept form is equal to

where
m is the slope or unit rate of the linear equation
b is the y-intercept or initial value of the linear equation
In this problem we have
The slope is equal to

The y-intercept is equal to
----> value of y when the value of x is equal to zero
substitute

For x=h hours
substitute

Answer:
A. No solutions
Step-by-step explanation:
2x-2x=-9
0= -9
Since 0 does not equal -9, there are no solutions.
B-y is the another factor
Answer:
20 feet below sea level
Step-by-step explanation: