What equation is equivalent to x + 8 = 21

Iwant to know what 3g+5h+4g-2h is my teacher is too selfish to tell us

Which value of m will create a system of parallel lines with no solution? y= mx - 6 8x - 4y = 12

Consider a bag that contains 220 coins of which 6 are rare indian pennies. for the given pair of events a and b, complete parts (a) and (b) below. a: when one of the 220 coins is randomly selected, it is one of the 6 indian pennies. b: when another one of the 220 coins is randomly selected (with replacement), it is also one of the 6 indian pennies. a. determine whether events a and b are independent or dependent. b. find p(a and b), the probability that events a and b both occur.