# Circles

How many different circles is determined by 9 points at the plane, if 6 of them lie in a straight line?

**Result****Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):**

**Showing 0 comments:**

**Be the first to comment!**

#### To solve this example are needed these knowledge from mathematics:

## Next similar examples:

- Prove

Prove that k1 and k2 is the equations of two circles. Find the equation of the line that passes through the centers of these circles. k1: x^{2}+y^{2}+2x+4y+1=0 k2: x^{2}+y^{2}-8x+6y+9=0 - Circles

In the circle with a radius 7.5 cm are constructed two parallel chord whose lengths are 9 cm and 12 cm. Calculate the distance of these chords (if there are two possible solutions write both). - Lines

In how many points will intersect 14 different lines, where no two are parallel? - Circle

Circle touch two parallel lines p and q; and its center lies on a line a, which is secant of lines p and q. Write the equation of circle and determine the coordinates of the center and radius. p: x-10 = 0 q: -x-19 = 0 a: 9x-4y+5 = 0 - Line

Straight line passing through points A [-3; 22] and B [33; -2]. Determine the total number of points of the line which both coordinates are positive integers. - Points collinear

Show that the point A(-1,3), B(3,2), C(11,0) are col-linear. - XY triangle

Determine area of triangle given by line 7x+8y-69=0 and coordinate axes x and y. - Perpendicular

Determine the slope of the line perpendicular to the line p: y = -x +4. - Center

In the triangle ABC is point D[1,-2,6], which is the center of the |BC| and point G[8,1,-3], which is the center of gravity of the triangle. Find the coordinates of the vertex A[x,y,z]. - Line

Line p passing through A[-10, 6] and has direction vector v=(3, 2). Is point B[7, 30] on the line p? - Angle

A straight line p given by the equation ?. Calculate the size of angle in degrees between line p and y-axis. - Slope

What is the slope of a line with an inclination -221°? - Square side

Calculate length of side square ABCD with vertex A[0, 0] if diagonal BD lies on line p: -4x -5 =0. - Slope

What is the slope of the line defined by the equation -2x +3y = -1 ? - Angle between lines

Calculate the angle between these two lines: ? ? - Perpendicular

What is the slope of the perpendicular bisector of line segment AB if A[-4,-5] and B[1,-1]? - Cone

If the segment of the line y = -3x +4 that lies in quadrant I is rotated about the y-axis, a cone is formed. What is the volume of the cone?