We have been given that professional plumbers suggest that a sewer pipe should be sloped 0.25 inch for every foot.
Therefore, we can find the slope as:
Therefore, the recommended slope for a sewer pipe is 
Y = mx + c
y = 2x + c
When x = 5 and y = 0,
0 = 2(5) + c
c = -10
y = 2x - 10
Answer:
x=8
Explanation:
The picture tells us that the triangle is equilateral (this means that each angle is 60°). We can assume this because each side has been marked with the same line.
Because each angle is equal to 60°, this means that:
7x+4=60
Now solve for x:
7x=56
x=8
50 x 3.14 = 157 i think this is the answer
