Question

On a number line, a number, b, is located the same distance from 0 as another number, a, but in the opposite direction. The number b varies directly with the number a. For example b = 2 3/4when a = –2 3/4. Which equation represents this direct variation between a and b?

Answer 1

a = -b

Explanation:

a = kb

-2 3/4 = k × 2 3/4

k = -1

a = -1 × b

a = -b