Amplitude = 3 in the above function
Hey there!
Let's set up an algebraic equation to represent this problem:

In order to get rid of the squared, we need to take the square root of both sides, therefore, our answer is:

Your answer is the square root of 20.
Hope this helps!
Symmetric Property of Equality
Area = Length x width
216 = 36 x width
width = 216 ÷ 36 = 6 inches
If you are suppose to find how much the spent all together then it would be 21. 09