a)
he charges a fixed cost of $12, meaning a one-time charge of 12 bucks, plus 1.50 for each window.
1 window................ 12 + 1.5(1)
2 windows............. 12 + 1.5(2)
3 windows............. 12 + 1.5(3)
4 windows............. 12 + 1.5(4)
x windows............. 12 + 1.5(x)

b)

Answer:
zero
Step-by-step explanation:
Answer: D
Step-by-step explanation:
Answer:
brainly.com/question/1820178
This is the same question as yours. There is a good explanation to it as well. Copy and paste it into your browser if you can't click it.
Answer:
x = 12, sides = 23
Step-by-step explanation:

Since
is equilateral, all three sides are equal. Therefore:
![\left[\begin{array}{l}y=2x-1\\y=5x-37\\y=x+11\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bl%7Dy%3D2x-1%5C%5Cy%3D5x-37%5C%5Cy%3Dx%2B11%5Cend%7Barray%7D%5Cright%5D)
Substituting y = x + 11:
![\left[\begin{array}{l}x+11=2x-1\\x+11=5x-37\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bl%7Dx%2B11%3D2x-1%5C%5Cx%2B11%3D5x-37%5Cend%7Barray%7D%5Cright%5D)
Solving for x:

Substituting x = 12:

Thus, <em>x</em> = 12 and the length of each side is 23.