Passwords for a certain computer system are strings of uppercase letters. a valid password must contain an even number of x’s. determine a recurrence relation for the number of valid passwords of length n. note: 0 is an even number, so abbc is a valid password. this counting problem is pretty tricky. here’s a good way to think about it: to make a good password of length n you can either (a) add any non-x to the end of a good password of length n − 1, or (b) add an x to the end of a bad password of length n − 1. for (b) you can use the good = total-bad trick to count the number of bad passwords of length n−1.

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1

answer: 1) twenty-seven times y

              2) twenty-seven multiplied by y

step-by-step explanation:

i believe its "c" because all of the other options include a but it could be d because there is a way of financing with cash at certain places but its uncommon.

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.