I WILL GIVE YOU BRAINLIEST IF YOU ANSWER THE WHOLE QUESTION.
PLEASE EXPLAIN EVERY STEP OF YOUR ANSWER CLEARLY.

4. Which of the following functions has a rate of change that stays the same?
A. y=1/3x^2
B. y=2x
C. y=-7x+9
D. y=x^2+1

B)   and     C)

Step-by-step explanation:

Once a linear function has a constant rate of change, you just have to find the linear functions. Also, the other ones are quadratic functions, and their graph are parabolas, which don't have a constant rate of change.

Considering

 has a constant positive rate of slope 2.  

has a constant negative rate of slope -7

here you hope this .

step-by-step explanation:

hypotenuse = √(15² + 8²)

=  √(225 +64)

=  √(289) = 17

sin(x) = cos(y) = 8/17

they are identical so long as you are doing the sine of one angle and the cosine of the only other angle that isn't the right angle.

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'.