(2(c+35)c)/(c+5)=60

Solution for (2(c+35)c)/(c+5)=60 equation:

D( c )

c+5 = 0

c+5 = 0

c+5 = 0

c+5 = 0 // - 5

c = -5

c in (-oo:-5) U (-5:+oo)

(2*c*(c+35))/(c+5) = 60 // - 60

(2*c*(c+35))/(c+5)-60 = 0

(2*c*(c+35))/(c+5)+(-60*(c+5))/(c+5) = 0

2*c*(c+35)-60*(c+5) = 0

2*c^2+10*c-300 = 0

2*c^2+10*c-300 = 0

2*(c^2+5*c-150) = 0

c^2+5*c-150 = 0

DELTA = 5^2-(-150*1*4)

DELTA = 625

DELTA > 0

c = (625^(1/2)-5)/(1*2) or c = (-625^(1/2)-5)/(1*2)

c = 10 or c = -15

2*(c+15)*(c-10) = 0

(2*(c+15)*(c-10))/(c+5) = 0

(2*(c+15)*(c-10))/(c+5) = 0 // * c+5

2*(c+15)*(c-10) = 0

( c+15 )

c+15 = 0 // - 15

c = -15

( c-10 )

c-10 = 0 // + 10

c = 10

c in { -15, 10 }