Guys can you please HELP!!?

What two criteria are needed for triangles to be similar

Will give let f(x)=2x and g(x)=[tex]2^{x}[/tex] graph the functions on the same coordinate plane. what are the solutions to the equation f(x)=g(x) ? enter your answers in the boxes x=[? ] or x=[? ]

Linda loans her friend $250 with a 5% monthly intrest rate. how much was the whole loan?