I am studying for a physics exam using a textbook written by my professor for my course. In it there is a step-by-step solution to a problem, and I cannot figure out how to go from one step to the next. Basically we arrived at
$$14t - 4.9t^2 = -4.9(t-2)^2$$
How (This is where he loses me) do we conclude $0.8t = 2.8$?
I am not sure what is going on to go from one step to the next. If I am ignorant to something simple, or if you have an explanation, or links to an explanation I would really appreciate the help.
By expanding one gets $$ -4.9(T-2)^2=-4.9\times T^2+4.9\times(4T)-4.9\times4=-4.9\: T^2+19.6\:T-19.6 $$ then the equation $$ 14T-4.9\: T^2=-4.9(T-2)^2 $$ reads $$ 14\:T-19.6\:T=-19.6 $$ that is (simplifying and dividing by $-7$) $$ 0.8\:T=2.8 $$ as announced.