Posted by **wong** on Wednesday, September 26, 2007 at 2:45am.

a straight line passing through the origin with slope m cuts the circle x^2+y^2-4x-2y-4=0 at A(a,b) and B(b,c).

A. Find a quadratic equation whose roots are a and c

ans: (1+m^2)x^2-(2m+4)x-4=0

B. if P is the mid-point of AB, find the coordinates of P in terms of m.

ans: P= (m+2)/(1+m^2), (m(m+2))/(1+m^2)

C. as m varies, the locus of P is part of a curve C. Find the equation of C.

ans: x^2+y^2=2x+y

I know how to do question A and question B, but how to do C? any idea?

## Answer This Question

## Related Questions

- math - i have more than one question so if u no any of the answers please tell ...
- Algebra - I'm suppose to write an equation with the following information: Line ...
- Math - I have a series of questions that I did. They lead up to the last ...
- Equation of a straight line. - 1. Find the equation of the line described in ...
- math help & correction - Problem #1 Is this correct or wrong? Find the slope of ...
- math - a) Determine an equation for the line with slope 3 and passing through ...
- NEED MAJOR HELP! *QUADRATIC EQUATIONS* - Write the equation for the circle with ...
- Algebra - Can someone check my answers? 1. Write the equation of the line that ...
- Algebra - Is it possible to find the slope of a line if the equation has two ys...
- ALGEBRA - Solve for y intercepts 7x+y=-2 Answer: Y = -2 7x + 2y = 4 Answer: Y...

More Related Questions