Question 993980
visit
http://edweb.tusd1.org/kukla/Mr_Kuklas_Website/Geometry/Worksheets/Circles/chap%20circ%20assign%2013.pdf


formula: {{{(x-h)^2+(y-k)^2=r^2}}}

some more
1.  An arch, in the shape of a circular arc, supports a pipeline (AB) across a river {{{18}}} meters wide. Midway, the suspending cable (CD) is 3 meters long. Find the radius of the arch. 

here is a sketch:

{{{drawing( 600, 600, -25, 25, -2, 10, 
circle(2,0,.12),circle(20,0,.12),circle(11,0,9),
locate(2,0,A),locate(20,0,B),locate(11,3.5,C),
line(2,0,20,0),line(11,0,11,2),locate(10,-0.5,18m),locate(9.5,1,3m),
 graph( 600, 600, -25, 25, -2, 10, 0)) }}} 
1.  
                             
{{{3x= 9^2}}}; where {{{x= chord }}}segment; 
{{{x= 27}}}; 
{{{(1/2)(27+3)=30/2=15 = radius }}}

answer: {{{15m }}}

2.
visit
http://www.shelovesmath.com/precal/parametrics-and-conics/#Circles

scroll down to
Applications of Circles

Problem: