Question 127987
J(J-2)/[J+(J-2)]=10
(J^2-2J)/(2J-2)=10 NOW CROSS MULTIPLY
J^2-2J=10(2J-2)
J^2-2J=20J-20
J^2-2J-20J+20=0
J^2-22J+20
USING THE QUADRATIC EQUATION:{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} WE GET:
J=(22+-SQRT[-22^2-4*1*20])/2*1
J=(22+-SQRT[484-80])/2
J=(22+-SQRT404)/2
J=(22+-20.1)/2
J=(22+20.1)/2
J=42.01/2
J=21.05 HOURS - TIME FOR JAMES TO PAINT THE HOUSE ALONE.
PROOF:
21.05*19.05/(21.05+19.05)=10
401/40.1=10
10=10