Aida applied the distributive property to write the equivalent expressions below. 15 + 21 = 3 (4 + 8)

What is Aida’s error?
Aida used 3 as the factor, which is not common to 15 and 21.
Aida did not correctly divide by the common factor to get (4 + 8).
Aida did not apply the correct operations to the expressions.
Aida wrote two expressions that are not equivalent.

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?

70 points ! pls 2. given the following two sets of data what is the union of the two sets and what is the intersection of the two sets. set a = {1, 2, 3, 4, 5, 6, 7, 8, 9} set b = {2, 4, 6, 8, 10, 12, 14} 3. given a regular deck of cards. describe a way of pulling cards that would create a dependent event and then one that would create an independent event. 4. what is the probability of drawing a red card and then drawing a spade without replacing the card that was drawn first?

Maria has $10,000 to invest in two accounts.he decides to invest one part in an account with 5% interest and the rest in an account with 8% interest. at the end of the year he has earned $702,50 in interest.¿how much did maria invest in the 8% account?