Question

The ordered pairs (2, -21) and (5, -45) are solutions to which of the following equations?

A. y=-8x-5
B. y=-8x+5
C. y=8x-5
D. y=8x+5

Answer 1

A. y = -8x -5

Explanation:

You will notice that when x increases from 2 to 5, y decreases from -21 to a number that is more negative. Thus only the first two answer choices are possibilities, since the others have a positive coefficient for x.

Trying the first given point in the first answer choice, we see that it works:

-21 = -8·2 -5

so, that is the equation we're looking for.

y = -8x -5