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 3/4 when a = -2 3/4. Which equation represents this direct variation between a and b?

O b=-a
O-b = -a. O b-a=0
Ob(-a) = 0

Answer 1

The answer of this question is C
Blablablabla

Answer 2

An equation that represents this direct variation between a and b is: A. b = -a.

In Mathematics and Geometry, a number line is a type of graph that is composed of a graduated straight line, which typically comprises both negative and positive numerical values that are located at equal intervals along its length.

This ultimately implies that, every number line would primarily increase in numerical value towards the right from 0 and decrease in numerical value towards the left from 0.

Since the number (b) is located the same distance from 0 as another number (a), but in the opposite direction and they vary directly, an equation that represents this direct variation between a and b can be written as follows;

b ∝ a

b = ka

2 3/4 = k(-2 3/4)

k = (2 3/4)/(-2 3/4)

k = -1

b = -a