-x/7 - 8 = 1, what does x equal?

Due to a packaging error, 4 cans labeled diet soda were accidentally filled with regular soda and placed in a 12 pack carton of diet soda. two cans were randomly selected from this 12 pack. what is the probability that both cans were regular soda?

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota

Which number can each term of the equation be multiplied by to eliminate the decimals before solving? 5.6j- 0.12=4+1.1j