Question

The recommended daily intake rdi a nutrients supplement for a certain age group is 800 mg per day actully supplements needs vary from person to person which absolute value inequality expresses the rdi plus or minus 50 mg

a. |x-800|≥50
b. |50-x|≤800
c. |x-800|≤50
d. |x-50|≤800

Answer 1

C

Explanation:

The recommended daily intake of a nutrients supplement for a certain age group is 800 mg per day.

Actully supplements needs vary from person to person plus or minus 50 mg.

This means the minimum value is 800 - 50 = 750 mg per day and the maximum value is 800 + 50 = 850 mg per day.

Let x mg be a possible daily amount of nutrients supplement. Then

`750\le x\le 850`

Subtract 800:

`750-800\le x-800\le 850-800\\ \\-50\le x-800\le 50`

This inequality can be rewritten using absolute value notation as

`|x-800|\le 50`