Find g(f(x)) if f(x)=2x and g(x)=x^2

Ten times the square of a non-zero number is eqaul to ninety times the number

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.

Clarence wants to buy a new car. he finds an ad for a car that costs 27,200 dollars. suppose his local sales tax is 7%. -how much would he have to pay? -what is the cost of the car including tax? -if clarence has 29,864 saved, can he pay cash to buy the car?