The perimeter of a rectangle is given by the formula,

We substitute,
and

into the above formula to obtain the expression,


We now group the x and y terms on the Left Hand Side of the equation to get.


We now divide through by 2 to get,

Therefore the width of the rectangle is

The answer I got was C = The car used 70 gallons of gas to go 3 miles.
Hope this helps.
Answer:
<h2>
67.7</h2><h2 />
Step-by-step explanation:
perimeter = semicircle (x2) + parallelogram side (x2)
= 1/2 π 12 (x2) + 15 (x2)
= 37.7 + 30
= 67.7
The constant is 3 because it has no variable.
The coefficient is 7b because it has a variable.