Question 910315
r*t=d
200/(60-c)+200/(60+c)=10/1
Multiply thru by 1*(60-c)(60+c)
200*1*(60+c)+200*1(60-c)=10(c^2-3600)
200*60+200*c+200*60-200*c=10*c^2-10*3600
12000+200*c+12000-200*c=10*c^2-36000
0=10*c^2-36000+(24000)+(0)*c
10*c^2+-12000=0
10*c^2+-12000=0
c=34.641

*[invoke quadratic "c",10,0,-12000]