Question

The water level is a number that indicates whether the level is above or below normal using positive or negative values. After a heavy storm, the water level of a lake is −5.6 feet. This level is 1/2 times 1.7 feet more than the previous water level.What was the previous water level?

Answer 1

Let's use the variable x to represent the previous water level.

If we add the previous water level by 1.7 and then multiply the result by 1/2, we have -5.6, so we can write the following equation:

$\frac{1}{2}\cdot(x+1.7)=-5.6$

Now, solving this equation for x, we have:

$\begin{gathered} x+1.7=-11.2 \\ x=-11.2-1.7 \\ x=-12.9\text{ ft} \end{gathered}$