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How do you find the area of a circle?. For Example. A circle has a diameter of 10 meters. What is the area of the circle?. In this lesson you will learn to find the area of a circle by exploring the relationship between a circle and a rectangle. Area of Rectangle = l x w. 5 cm. 9 cm.
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How do you find the area of a circle? For Example A circle has a diameter of 10 meters. What is the area of the circle?
In this lesson you will learn to find the area of a circle by exploring the relationship between a circle and a rectangle.
Area of Rectangle = l x w 5 cm 9 cm A = 5cm x 9cm A = 45 cm2
Multiplying a number or variable by itself is known as squaring it. 9 x 9 = 92= 81 r x r = r2
Remember the Order of Operations. Exponents come before multiplication. A = (3.14)(4)2 Wrong Correct A = (12.56) 2 A = (3.14)(16) A = 157.7536 A = 50.24
A pizza has a radius of 9 inches. What is the area of the pizza? r = 9 inches
πr r Area of a Circle =πr2
A = π(9in.)2 A = 3.14(81in.2) A = 254.34in.2
Find the area of a circle with a diameter of 10 meters. Do not approximate pi. A = π(5m)2 A = 25πm2
In this lesson you have learned to find the area of a circle by exploring the relationship between circles and rectangles.
What is the area of a circle that has a radius of 6 cm? Use 3.14 for pi.
Susan drew a circle with a radius of 4 inches and Ellen drew a circle with a radius of 8 inches. Ellen said “since the radius of my circle with twice the radius of your circle, the area of my circle is twice the area of your circle.” Is Ellen’s statement correct? If not, explain what Ellen could say instead.
A circle is inside of a square, as shown below. The edges of the square each touch a point on the circle. If the square has an area of 16 square meters, what is the area of the circle?
A circular pizza can feed 4 people if it has an area of at least 200 square inches. A pizza from Joe’s Pizza has a radius of 9 inches. Is it enough to feed a family of 4?