SOLUTION: Determine the equation of the circle whose radius is 5, center on the line x=2 and the tangent to the line 3x-4y+11=0.

Algebra ->  Circles -> SOLUTION: Determine the equation of the circle whose radius is 5, center on the line x=2 and the tangent to the line 3x-4y+11=0.      Log On


   



Question 1016038: Determine the equation of the circle whose radius is 5, center on the line x=2 and the tangent to the line 3x-4y+11=0.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Create two lines that are parallel to the tangent line.
These two lines will be 5 units away from the tangent line, one above, one below.
Once you have those lines, you can find the intersection point of those lines with x=2 to find the center of the circles.
The tangent line is
3x-4y%2B11=0%7D%7D%0D%0A%7B%7B%7B4y=3x%2B11
y=%283%2F4%29x%2B11%2F4
You can calculate the difference in y-intercepts given the distance, d, between parallel lines using the formula,
d=DELTA%2Ab%2Fsqrt%28m%5E2%2B1%29
5=DELTA%2Ab%2Fsqrt%28%283%2F4%29%5E2%2B1%29
DELTA%2Ab=sqrt%2825%2F16%29%2A5
DELTA%2Ab=%285%2F4%29%2A5
DELTA%2Ab=25%2F4
So the two lines would be,
y%5B1%5D=%283%2F4%29x%2B11%2F4%2B25%2F4=%283%2F4%29x%2B36%2F4=%283%2F4%29x%2B9
y%5B2%5D=%283%2F4%29x%2B11%2F4-25%2F4=%283%2F4%29x-14%2F4=%283%2F4%29x-7%2F2
So when x=2,
y%5B1%5D=%283%2F4%292%2B9=3%2F2%2B18%2F2=21%2F2
y%5B2%5D=%283%2F4%292-7%2F2=3%2F2-7%2F2=-2
So then the circles are,
%28x-2%29%5E2%2B%28y-21%2F2%29%5E2=25 and
%28x-2%29%5E2%2B%28y%2B2%29%5E2=25
.
.
.
.