PLEASE HELP What is the equation of a line through the points (0,9) and (3, 0)?

Because m =9-0/0-3;y=-3x+9
Because m =9-0/0-3;y=-3x+3
Because m =3-0/0-9;y=-1/3x+9
Because m =3-0/0-3;y=-1/3x+3

The number of revolutions of two pulleys is inversely proportional to their diameters. if a 24-inch diameter pulley making 400 revolutions per minute is belted to an 8-inch diameter pulley, find the number of revolutions per minute of the smaller pulley.

What are “like terms”? why can we only add like terms?

Find the domain of the following expression: 1/(√x)-2