Is 9x-6y=-20 and -3y=2x-11 parallel, perpendicular, or neither

This is the number of parts out of 100, the numerator of a fraction where the denominator is 100. submit

If you flip a coin 3 times, what is the probability of flipping heads 3 times? a. p(3 heads) = 3/8 b. p(3 heads) = 1/6 c. p(3 heads) = 1/8 d. p(3 heads) = 1/2

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.