Question

Suppose a diver dove from a diving platform 4 feet above the water and stopped at –8 feet to pick up some scallops. Which expression models this situation and tells how far below the diving platform she is?

A. –4 + |–8|
B. |4| + |8|
C. 4 – |–8|
D. 4 + |–8|

Answer 1

Answer: Option D.

Explanation:

By definition, the absolute value of a number is its distance from 0 on a number line. We know that the distances cannot be negative. Then:

`|-a|=a`

We can assume that the water is at level 0.

We know that the diver dove from a diving platform, which is 4 feet above the water, and then she stopped at -8 feet to pick up some scallops.

This indicates that she stopped at 8 feet below the water.

Therefore, in order to find how far below the diving platform the diver is, we must add 4 feet and the absolute value of -8 feet.

Then, the expression that models this situation is:

`4+|-8|`

Notice that it matches with the expression shown in Option D.