Question

Which situation CANNOT be represented by this equation? -1\4x + 14 = 8

A) A hot-air balloon has a 14-foot diameter that each 1\4 of an hour gets steadily smaller. At what rate, x, does the balloon have to shrink per hour before it has shrunk to a diameter of 8 feet?
B)A hot-air balloon has a 14-foot diameter that is getting smaller at a rate of 1\4 foot per minute. How many minutes, x, will it take before the balloon has shrunk to a diameter of 8 feet?
C)A hot-air balloon has an 8-foot diameter that is changing at a rate of 1\4 foot per minute. How long in minutes, x, will it take until the balloon has a diameter of 14 feet?

Answer 1

probably C)
it starts with 8-foot diameter, and it is supposed to get smaller

This is just a theory

Answer 2

Situation (C) cannot be represent by the given equation.

Explanation:

In (A), the balloon shrinks at the rate x. So, each 1/4 of an hour, its diameter reduces by the amount 1/4x.

So, it correctly represents the given equation.

In (B), the diameter reduces to 1/4 every minute.

So, in x minutes the amount reduced = 1/4x.

So, it also correctly represents the given equation.

In (C), the diameter reduces to 1/4 foot per minute but its original measurement is 8 foot and we are asked to find the expression when it is 14 feet.

So, the correct equation for this situation is 1/4x + 8 = 14.