SOLUTION: Find an equation of the line tangent to the circle (x−3)2+(y−3)2=25 at the point (6,7).

Algebra ->  Functions -> SOLUTION: Find an equation of the line tangent to the circle (x−3)2+(y−3)2=25 at the point (6,7).      Log On


   



Question 644120: Find an equation of the line tangent to the circle (x−3)2+(y−3)2=25
at the point (6,7).

Found 2 solutions by reviewermath, MathLover1:
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
The center of the circle %28x+-+h%29%5E2+%2B+%28y+-+k%29%5E2+=+r%5E2 is (h,k).
Therefore the center of %28x+-+3%29%5E2+%2B+%28y+-+3%29%5E2+=+25 is (3,3).
The tangent line is perpendicular to the segment joining (6,7) and (3,3).
slope of the segment joining (6,7) and (3,3) = %283+-+7%29%2F%283+-+6%29+=+4%2F3.
negative reciprocal of 4/3 = -3/4
Equation of tangent line:
y+-+7+=+%28-3%2F4%29%28x+-+6%29
Answer: highlight%28y+=+%28-3%2F4%29x+%2B+23%2F2%29.
Here's the graph:

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
given:
the circle %28x-3%29%5E2%2B%28y-3%29%5E2=25
and the point (6,7)
A circle with center (a,b) and radius r has equation
(x - a)^2 + (y - b)^2 = r^2
Your circle has equation
(x - 3)^2 + (y - 3)^2 = 25
and hence a+=+b+=+3 and r+=+5. Thus your circle has (center (3,3) and radius r=5.
a plot of the circle
Solved by pluggable solver: PLOT any circle and describe it

Diameter: d+=+2r+=+2%2A5+=+10.
Area: area+=+pi%5Cr%5E2+=+pi%2A5%5E2+=+78.5398173497349
Perimeter: perimeter+=+2%5Cpi%5Cr+=+2%5Cpi%2A5+=+31.415926939894






at the point (x1,y1)=(6,7)
the tangent to a circle at the point (x,y) is:
%28x1-a%29%28x-a%29+%2B%28y1-b%29%28y-b%29+=r%5E2
at the point (6,7)
%286-3%29%28x-3%29+%2B%287-3%29%28y-3%29+=25
3%28x-3%29+%2B4%28y-3%29+=25
3x-9+%2B4y-12+=25
4y=-3x%2B9%2B12%2B25
4y=-3x%2B46
y=-%283%2F4%29x%2B46%2F4
highlight%28y=-%283%2F4%29x%2B23%2F2%29..........equation of the line tangent to the circle
follow this link and you will see image of your circle and tangent:
http://imageshack.us/photo/my-images/407/capture831201285126pm.jpg/