Solve X + X squared for X =3

Who long does it take to drive 150 miles at 45 miles per hour

Apassenger train and a freight train leave san jose at 3pm, traveling in the same direction. the passenger train is going three times as fast as the freight train. at 6pm they are 240 miles apart. how fast is each travelling? explain your answer and show your

If the perimeter of the square equals the perimeter of the regular pentagon. each side of a pentagon is 16cm long. how long is each side of the square?