Question

Laurie is trying to stay within 10 feet of her current diving depth of –30 feet (with regard to sea level) so that the light is still good but she can be close to the sea life during her scuba dive. Which two equations can be used to find the minimum and maximum depths Laurie wants to stay between?

-30 - x = 10 and -30 - x = –10
-30 + x = 10 and -30 + x = –10
x + 10 = 30 and x + 10 = –30
x – 10 = 30 and x – 10 = –30

Answer 1

Choose: -30 - x = 10 and -30 - x = –10.

Solve: -30 - x = 10 → -x = 40 → x = -40 (minimum depth).
-30 - x = -10 → -x = 20 → x = -20 (maximum depth).

So Laurie should stay between -40 ft and -20 ft.