Need with my problem of the day it’s confusing i’m not good at math : | question in picture

Combine like terms to make a simpler expression 3z+z

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.

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?