A rose garden is formed by joining a rectangle and a semicircle, as shown below. The rectangle is 32 ft long and 20 ft wide. Find the area of the garden? Use the value 3.14 for pie and do not round your answer.

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1 Answer
Feb 12, 2018

The area of the garden is #797 ft^2#.

Explanation:

First, let's find the area of the rectangle.

We know that the area of a rectangle is the length times width, or #20 * 32# in this example:
#20 * 32 = 640#

So the area of the rectangle is #640 ft^2#.


You may not know the area of a semicircle, but that's fine #-# we know the area of a circle, or #pir^2#.

Since the area of a semicircle is half the area of a circle, we just do the area of the circle divided by #2#:
So the area of a semicircle is #(pir^2)/2#.

The question asks for #pi# to just be #3.14#, so instead the equation is #A = (3.14r^2)/2#

The picture gives the diameter of the circle.

To find the radius, or #r#, we divide the diameter by #2#:
#20/2 = 10#

Now we can solve for the area of the semicircle:
#(3.14(10)^2)/2#

#(3.14(100))/2#

#314/2#

#157 ft^2#

Now that we now the areas of the rectangle and semicircle, we can add them up to find the area of the rose garden:
#640 + 157 = 797 ft^2#