6th grade dignified practice 4 4 sector area 1

Is this the question?

The fan radius is 2, the central angle is 60°, and the fan area is found.

The diameter of the fan is 6 and the central angle of the circle is 90°, and the area of the fan is found.

Fan Radius2 Arc Length Find the fan area.

Sector radius 6Arc length Find the sector area.

The sector area, the central angle of the circle is 60°, and the radius of the sector is found.

Sector Area Radius3 The central angle of the sector is.

Sector area Radius 10 Sector arc length is.

The radius of the sector is 10 and the central angle of the circle is 18°.

1 l= 2 s= 3 The area of the circle is 314 square meters 4 Sector perimeter The radius of the sector remains unchanged. If the central angle of the circle is reduced to 1/2 of its original size, then its area is ( ) Answer: The radius of the sector remains the same.

The central angle of the circle is reduced to 1/2 of the original size, and its area is (1/2 of the original size).

If the diameter of the circle is 40 cm, the area of the sector with an arc length of 60 cm is: 60 20 2 600 (cm).

Answer to question 1: square centimeters.

Answer to the second question: square centimeters.

Answer to question 3: square centimeters.

Answer to question 4: square centimeters.

Question 6 answer: 320°

Question 7 Answer: Square centimeters.

Answer to question 8: b

Answer to Question 9: a

Connecting the two vertices in the shadow section, the leaf shadow is divided into 2 equal parts, and the area of 1 part is: square centimeters, so the area of all shadows is: square centimeters.

Solution: square centimeters, the area of all shadows is: square centimeters.

In the first step, calculate the area a of the square

In the second step, calculate the area b of 1 4 circles

In the third step, subtract area B from area A to get area C

In the fourth step, A-C obtains the final required shaded area.

Add the area of two quarter-circles and subtract the square area to get the shaded area.

Only ideas are provided, not specific solutions.

In the first step, calculate the area a of the square

In the second step, calculate the area b of 1 4 circles

In the third step, subtract area B from area A to get area C

In the fourth step, A-C obtains the final required shaded area.

Summary. So the radius is 16, and the area of the three sectors is: square centimeters.

Hello, the circumference of each 1 4 sector is centimeters, find what is the total area of the three sectors, the specific calculation process is as follows:

Because the circumference of Wu Yu is fan-shaped: r+r+2 r 4 2r+ r 2 Gao Tang Song Qi Zheng, the radius is 16, and the area of the three fans is: square centimeters.

What does that 2 r 4 mean.

A quarter of the circumference of the circle.

Think of the fan shape as a circle of 1 4.

s=πr^2*1/4

So the sector area is.

s△=6*6÷2

The triangle has an area of 18

So the shaded part is.

A sector is a quarter of a circle, the radius is known, what will be the area of the entire sector? The white triangle is an isosceles right angle, and the waist is the radius of the fan, and the area will be? The shadow area is the sector area minus the triangles.

Draw a square, use your compass at any point, adjust the compass angle to be as long as the side length of the square, and draw a fan inside the square.

So you understand, because the circumferential angle is 360°, and the angle of this sector is 90°, which is the area of a quarter circle.

The area of the square is equal to the square of the side length = 48 square centimeters, then the side length is 48 = 4 3Then the fan radius is 4 3

Using the area formula, you can find a quarter of a circle with a radius of 4 3!

I don't know how to ask, ask!

The fan shape is considered as 1 4 circles, and the radius is the length of the sides of the square. I think you must know how to find the area of a circle. 48 is equivalent to the square of the radius. Multiply by is the area of the circle, multiply by 1 4.

48* （cm²）

Clear enough, right?! I remember doing that when I was in sixth grade.

You should use open square for this question! The area of the square is 48, and the four sides are the same length, and only four times the root number three times times the four root number three equals forty-eight ah......It's not an elementary school question, is it, brother......

The radius of the sector does not change. The central angle of the circle is reduced to 1/2 of the original size, and its area is 1/2 of the original size

If the diameter of the circle is 40 cm, the area of the sector with an arc length of 60 cm is: 60 20 2 600 (cm).

It's best to divide it into 13 questions to ask, and there will be a lot of people doing it soon. Also for the subject of the lead wheel to sell want to Huai teasing, one.

Individuals do so much, tired!