Chris T
Into to College Math (H)
Chapter 10-8
Tangents and Normals to the Conic sections
if your are given a circle do you know how to find a line that is tangent to one point on that circle?
When given the equation of a circle it is fairly simple to find the equation of a line that is tangent to that circle.
First take the equation of the circle and the point you want the line to be tangent to.
( x)2 + (y)2=149 (-12,3)
To find the slope of the line.
If the standard form of the equation is (x-h) 2+
(y-k)2 =r2 and the equation for
the slope of line tangent to a circle is
m=-(x-h)/(y-k) then.......
m=-(-12-0)/(3-0)
m= -4
Now use the formula x(x1)+ y(y1)-r2=0 to find the standard form of the equation.
x(-12)+y(3)-(&149)2=0
-12x+3y-149=0
3y-12x=149
or you can put it in point slope form
y=4x+149/3
"it is easy to hate and it is difficult to love. this is how the whole scheme of things works. all good things are difficult to achieve; and bad things are easy to get" integrity
-Confucius
this quote came from
www.Quotationspage.com/quotes/confucius