4x+20y=140 x+3y=146 equation 1 is modeled for the percentage of never married americans, y, x years after 1970 and equation 2 is modeled for the percentage of married american adults y, x years after 1970

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Which best explains why this triangle is or is not a right triangle ?

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?