6/7x - 2/5y + 5/7(y+x)

Question and answers are in the attached picture. you so much in advance.

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.

Consider the graph of the exponential function y=3(2)×