In the function y = 12.00x + 50, y represents the cost of carpet by the square yard and x represents the number of square yards. how much does the cost increase for square yard of carpet purchased?
a) x
b) $12.00
c) $50.00
d) $62.00

so this is very simple.

if f(x)=12x +50, and we want to know how much the cost goes up per square yard, we look at the relationship.

if the coefficient of x is 12, the cost will go up $12 per square yard.

it is NOT 62 because the 50 is a one time thing that is only added one time. think about it like having the price be $50 at 0 yards. it's almost like a flat fee. for 1 yard its 62, 2 its 74, etc. it goes up 12 each time. additionally, it's not x because x is the amount of yards, not the cost of a yard. it is not 50 because 50 is added, and is not in relationship to x.

so, the answer is b.

hope I helped.

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.