Find the area of the shaded region

Mathematics

2 answers:

Darina [25.2K]3 years ago

7 0

Answer:

Area = 56.549 cm^2

Step-by-step explanation:

To find the area, simply create a ratio for the portion of the shaded region to the area of a complete circle.

The area of a whole circle is A = πr^2. Note, the sum of degrees of a circle is 360. With this in mind, we can create our ratio.

A = (80/360)πr^2

A = (80/360)π(9cm)^2

A = 56.549 cm^2

Gala2k [10]3 years ago

7 0

Answer: 56.52

Step-by-step explanation: first we have to find the are of the circle. We can use the formula:

A=πr²

We can use 3.14 for π and 9 for radius and write our new equation A=3.14*81

We get area= 254.34 cm

Then we need to find the area of the shaded. 80 degrees is 2/9 of 360 degrees. So the shaded area is 2/9 of the total area.

Using this we can make an equation: 254.34*2/9= 56.52

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