A rose garden is formed by joining a rectangle and a semicircle, as shown below. The rectangle is 31 ft long and 20 ft wide. If the gardener wants to build a fence around the garden, how many feet of fence are required?
(Use the value for 3.14 , and do not round your answer. Be sure to include the correct unit in your answer.)

Respuesta :

Answer:

133 ft

Step-by-step explanation:

Given in the question,

length of the rectangle = 31 ft

width of the rectangle= 20 ft

diameter of semicircle = 20 ft

radius of semicircle = 20/2 ft = 10 ft

Formula to use:

perimeter of rectangle + perimeter of semicircle

perimeter of rectangle = 2(l+w)

perimeter of semicircle = 1/2(2πr)

Plug values in the formula above

2(31 + 20) + 3.14(10)

133.4 ft

≈ 133 ft

Answer:The area of the garden is

797

f

t

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

f

t

2

.

You may not know the area of a semicircle, but that's fine

we know the area of a circle, or

π

r

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

π

r

2

2

.

The question asks for

π

to just be

3.14

, so instead the equation is

A

=

3.14

r

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

f

t

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

f

t

2