## 1.

The Correct Answer is (C) — We know that $\sqrt{-64}&space;=\sqrt{64}i&space;=&space;8i$, so the correct answer choice is (C).

## 2.

The Correct Answer is (C) — As with most “ NOT” or “ EXCEPT” questions, we have to test every answer. We know that $\sqrt{3136}i&space;=&space;\sqrt{64&space;\times&space;49}i=&space;8\sqrt{-49}$ so A is okay. $7\sqrt{64}i&space;=\sqrt{49&space;\times&space;64}i&space;=&space;8\sqrt{-49}$ so we know choice B is okay, too. $\sqrt{56}i&space;=\sqrt{7\times&space;8}i$ and we know this is not equal to $8\sqrt{-49}$so we know C is the only one that is not true.

## 3.

The Correct Answer is (B) — We can solve this problem by adding like terms, which means adding the integers and imaginary numbers separately: (8+2i) + (2+8i) = 8 +2 +2i +8i = 10 + 10i. The correct answer choice is (B).

## 4.

The Correct Answer is (B) — In order to solve this problem, we need to first simplify the numerator by turning it into imaginary number form: $5\sqrt{-4}&space;=&space;10i$. Divide this number by 2i, and recall from the question that 5= 3w Divide both sides by 3 to get, and we have our answer: w= 5/3. The correct answer choice is B.

## 5.

The Correct Answer is (D) — We can solve this problem by simply plugging in the provided values into corresponding variables: $Z&space;=&space;2+&space;5i^{3}=&space;2-5i.$ The correct answer choice is D.

## 6.

The Correct Answer is (A) — Use the values given in the question to solve the equation for Z:

$Z&space;=&space;0&space;+&space;(1)i^{10}=&space;-1.$ The only answer choice that is not equal to -1 is A because $i&space;=&space;\sqrt{-1}.$

## 8.

The Correct Answer is (4) — In order to solve this problem, we need to first simplify the left side of the equation: (49 - 2i) - (48 - i) = 1 - i. Now, we can solve for x: 1 - i = (x -4i)/4, therefore 4 - 4i = x - 4i, therefore 4 = x.

## 9.

The Correct Answer is (1) — We can solve this problem by foiling the left side of the equation and then solving for x: (1 + i)(1- i) = 2 = 2x, therefore x = 1.