Solve the system by substitution

From the figure and statement provided, select the proper to prove statement. through a point outside a line one line can be drawn parallel to the line. mn= ab ab + bc= ac mis parallel to ! ab=bc als parallel to b

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.

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.