Which direct variation equation includes the point ( -9, 15 )

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.

Which equation represents a direct linear variationa. y=x2b. y=2/5xc. y=1/xd. y=x+3

F. a fair coin is thrown in the air four times. if the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss? a. 0 b. 1/16 c. 1/8 d. 1/2