What do you need help with? I'm looking for points mate..
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: The top left one is -3, 6 bottom right is -6, 3
Step-by-step explanation:
s = 2(lw + lh + wh)
Divide each side by 2 : s/2 = lw + lh + wh
Subtract 'lh' from each side: s/2 - lh = lw + wh
Combine the 'w' terms: s/2 - lh = w(l + h)
Divide each side by (l + h): (s/2 - lh) / (l + h) = w