1. If k and h are constants and x^2 + kx + 7 is equivalent to (x+1)(x+h), what is the value of k?

(a) 0

(b) 1

(c) 7

(d) 8

2. If k is a positive integer, which of the following must represent an even integer that is twice the value of an odd integer?

(a) 2k

(b) 2k+3

(c) 2k+4

(d) 4k+1

(e) 4k+2

i thought that the answer was (a) but the actual answer is (e) and i don't know why

3. If x and y are positive integers and 4(2^x) = 2^y, what is x in terms of y

(a) y-2

(b) y-1

(c) y

(d) y+1

(e) y+2

i didn't know how to solve this because what i did was:

8^x = 2^ y

2^3x=2^y

3x=y

x=y/3

but there was no option for that..

4. If n/(n-1) x 1/n x n/(n+1) = 5/k for positive integers n and k, what is the value of k?

(a) 1

(b) 5

(c) 24

(d) 25

(e) 26

i simplified the whole thing down to:

k = 5n + 5/n

and i do not know what to do next

thank you so much!