We know the distance formula is

9)
Here A( -4,2) and B(1,4)
So length of AB
= 
Also C(2,1)
Length of BC
= 
So we can see that length of AB is not equal to length of BC
11.
Now AB = 
Also C(2,-1) & D(4,4)
Length of CD
= 
Yes AB = CD
For the first step you need to convert between feet in real life and feet in the cartoon drawing. 1/2 inch in cartoon is 3 feet in real life, so 1 foot in real life was 1/6 inch in cartoon. Her hair was 21 feet in real life, therefore it was 21/6, or 7/2 inches long in the cartoon. For the second step you need to explain what I just said, In your own words! Please do not simply copy down my solution.
Sorry just coming for the points
Answer:
a) Revenue function = 1.299r + 1.379p
where: r = gallon of unleaded regular gasoline and p = gallon of regular unleaded premium gasoline
b) cost function = 1.219f + 1.289p
c) profit function = (1.299r + 1.379p) - (1.219f + 1.289p) = 1.299r - 1.219r + 1.379p - 1.289p = 0.08p + 0.09p
d) total profit = (0.08 x 100,000) + (0.09 x 40,000) = $8,000 + $3,600 = $11,600