The arc length and area of a sector are both 5. Find the degree of the central angle of the sector

The arc length and area of a sector are both 5. Find the degree of the central angle of the sector

Let the degree be α, the arc length be equal to 2 π R * α / 360, and the area be equal to π R & # 178; * α / 360. Since they are all equal to 5, r = 2, that is, α = 5 / (4 π) * 360 is about 143.31 degrees

The arc length and area of a sector are both 5, and the arc number of the central angle of the sector is 5______ ．

Let the arc number of the central angle of the sector be α and the radius be r. ∵ the arc length and area of a sector are 5, ∵ 5 = α R, 5 = 12 α R2, and the solution is α = 52

The equation of a circle passing through three points o (0,0) M1 (1,1) m2 (4,2)
（0-a）²+（0+b）²=r²
（1-a）²+（1-b）²=r²
（4-a）²+（2-b）²=r²
Can't solve the linear equation of three variables

You can change the yuan... A plus B equals R. after a = 4, B = minus 3

Mathematics compulsory 2: solve the equation of the circle of three points o (0,0), M1 (1,1), M2 (4,2). It's the + 2, + 20 after F. how do you get it?
Solve the equation of circle with three points o (0,0), M1 (1,1), M2 (4,2)
According to compulsory 2 of PEP a edition, the following system of linear equations with three variables is listed:
F=0
D+E+F+2=0
4D+2E+F+20=0
After substituting those three coordinates, it is obvious that there is no one that can be substituted into F,
I can't figure out where all the numbers added after f come from. They are + 2, + 20 after F

X ^ 2 + y ^ 2 + DX + ex + F = 0 is a general equation of circle
F = 0 is the result of introducing o (0,0)
M1 (1,1) is 1 + 1 + D + e + F = 0, that is d + e + F + 2 = 0
M2 (4,2) is 16 + 4 + 4D + 2E + F = 0, that is 4D + 2E + F + 20 = 0
Hope to help you! ↖ (^ω^) ↗

Find the equation of the circle of three points a (0,0) B (1,1) C (4,2), and find the radius length and center coordinates of the circle

The central point of line AB and line AC can be obtained respectively. The linear equation that passes through the central point and is perpendicular to AB and AC can be obtained by simultaneous equations. The distance from the central coordinate to point a is the radius

Find the equation of the circle with three points a (0,2) B (- 1,1) C (- 2,2), and find the center coordinates and radius length of the circle
We should take concrete steps

Let the center of the circle be (x0, Y0), the radius be r, and the circle equation be (x-x0) &# 178; + (y-y0) &# 178; = R & # 178;
Then: (0-x0) & 178; + (2-y0) & 178; = R & 178; (1)
(-1-X0)²+(1-Y0)²=r² (2)
(-2-X0)²+(2-Y0)²=r² (3)
(3)-(1)：(X0+2)²-X0²=0,4X0+4=0,x0=-1
(1)-(2)：(Y0-2)²-(Y0-1)²+X0²-(X0+1)²=0
Y0²-4Y0+4-Y0²+2Y0-1+X0²-X0²-2X0-1=0
-2Y0-2X0+2=0,Y0=1-X0=1-(-1)=2
Substituting (1): R & # 178; = 1, r = 1
So the center of the circle is (- 1,2) and the radius length is 1

Find the equation of the circle passing through three points (0,0) (1,1) (4,2), and find the radius and center coordinates of the circle
Such as the title, rescue field such as fire fighting

Let the equation of a circle be (Y-A) & sup2; + (X-B) & sup2; = R & sup2;
Substitute the three-point coordinates into:
a²+b²=r²
(1-a)²+(1-b)²=r²
(4-a)²+(2-b)²=r²
Solve the equations a = 4; b = - 5; r = √ 41
Center coordinates (4, - 5), radius √ 41

The equation of the circle of three points a (0,0) B (2,2) C (3,1) is solved, and its center coordinates and radius are obtained

Let the coordinates of the center of the circle be (a, b)
The coordinates can be calculated as (3 / 2,1 / 2), so the radius is √ 10 / 2
The equation is (x-3 / 2) 2 + (Y-1 / 2) 2 = 5 / 2

Given that a circle passes through points a (2, - 3) and B (- 2, - 5), find (1) if the area of the circle is the smallest, find the equation of the circle (2) if the center of the circle is in a straight line

(1) If the area of the circle is the smallest, then the circle is a circle with ab as the diameter
You can use the formula, or the center point can be the center of the circle
(x-2)(x+2)+(y+3)(y+5）=0
The intersection of abd's middle vertical line and known straight line is the center of the circle, and then the radius is calculated

Given a circle through two points 2, - 3 - 2, - 5, the center of the circle on the line x-2y-3 = 0 equation?

Let the center of the circle be (a, b). Then the equation x-2y-3 = 0a-2b-3 = 0 (1) is satisfied. If the distance between two points on the circle and the center of the circle is equal, then according to the distance formula. (2-A) ^ 2 + (B + 3) ^ 2 = (- 2-A) ^ 2 + (B + 5) ^ 2 (2) has the above (1) (2) equations. If a and B are solved, the equation of the circle is (x-a) ^ 2 + (y-b) ^ 2 = C