I need help on question 1-6

Ahigh definition tv cost $800 with a down payment of 2/5 of the cost. how much is left to pay, in dollars after the down payment has been made?

Need ! give step by step solutions on how to solve number one [tex]\frac{9-2\sqrt{3} }{12+\sqrt{3} }[/tex] number two [tex]x+4=\sqrt{13x-20}[/tex] number three (domain and range) [tex]f(x)=2\sqrt[3]{x} +1[/tex]

Which functions shave a maximum and are transformed to the left and down of the parent function ,check all that apply f(x) = x2? p(x) =14 (x+7)2 + 1