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When you substitute $y=x+1$ in the equation of the circle, you get a quadratic equation for $x$. Solve that quadratic equation using the "$\sqrt{b^2-4ac}$" formula (the solution will involve the constant $m$). If $b^2-4ac$ is positive then there are two solutions to the equation, meaning that the line cuts the circle in two points. If it is negative then there are no solutions, meaning that the line misses the circle. But if it is zero then there is just one (repeated) solution, meaning that the line is tangent to the circle.The circle x^2 +y^2 -4x+2y+m=0 is tangent with the line y=x+1.Find m.
p.s : I know that o should solve it from the equations of two lines but i really get confused when i substitute the y :/ .
Thanx![]()
Maybe I understand your remark about the two lines completely wrong, but here comes a way to use actually two lines:The circle x^2 +y^2 -4x+2y+m=0 is tangent with the line y=x+1.Find m.
p.s : I know that o should solve it from the equations of two lines but i really get confused when i substitute the y :/ .
Thanx![]()