Can you please add the picture with the problem, then I will answer your question ?
Answer:
A. The slope of Birch Street is 0. To be perpendicular to Elm, Birch would have to have a slope of negative 4/7.
Step-by-step explanation:
I had this same question on Gradpoint and got it correct.
Usually a ratio will compare two numbers by division
Differences:
point slope form of line:
(a) equation is 
where m is slope and (x1,y1) is a point
(b)This equation of line can be determined when two points are given
(x1, y1) and (x2,y2)
slope intercept form of line:
(a) equation is 
where m is a slope
b is y-intercept
(b)This equation of line can be determined when y-intercept and slope are given
Similarilties:
(a) both are equation of straight line
(b) slope is always constant in both
6x + 3y = 79.5
3x + 2y = 41 y = -3/2x + 41/2 y = -1.5x + 20.5
6x + 3(-1.5x + 20.5) = 79.5
6x - 4.5x + 61.5 = 79.5
1.5x + 61.5 = 79.5
1.5x = 18
x = 12
Each shirt costs $12.
Now insert that number into the x to find the cost of each tie.
3(12) + 2y = 41
36 + 2y = 41
2y = 5
y = 2.5
Each tie costs $2.50.
