Question

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

Answer 1

Answer:

B)$y=2x$   and     C) $y=-7x+9$

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 $f(x)=y$

$f(x) = 2x$  has a constant positive rate of slope 2.  

$\frac{dy}{dx}=2$

$f(x)=-7x+9$ has a constant negative rate of slope -7

$\frac{dy}{dx}=-7$