Math 9 Module 2

1. True or False?
(-3)⁵ will give a negative answer

True

False

a negative number to an odd exponent will give a negative answer

Explanation

a negative number to an odd exponent will give a negative answer

2. A square has an area of 36 m².
What is the length of each side?

30 meters

9 meters

6 meters

25 meters

length of a square's side = square root of the area

Explanation

length of a square's side = square root of the area

3. Which one of the following shows 13500000 in scientific notation?

Note: ^ means the next number is an exponent.
so:
10³ = 10^3

1.35 x 10^7

135 x 10^5

0.135 x 10^4

1.35 x 10^-7

the decimal needs to be moved 7 places to the left to get to 1.35 - 7 left is written as 10^7 (positive)

Explanation

the decimal needs to be moved 7 places to the left to get to 1.35 - 7 left is written as 10^7 (positive)

4. True or false?

3^-3 = 1
27

True

False

The given statement is false. The subtraction of 3 from 3 is equal to 0, not 1. Therefore, the correct answer is False.

Explanation

The given statement is false. The subtraction of 3 from 3 is equal to 0, not 1. Therefore, the correct answer is False.

5. Which of the following is the standard form of this number:
1.44 x 10^-5

1440000

0.00000144

14400000

0.0000144

negative exponent means decimal moves to the right 5 places

Explanation

negative exponent means decimal moves to the right 5 places

6. Evaluate:
(4a²b³c⁴)(3ab²c³)

12a^2b^6c^12

7a^2b^6c^12

12a^3b^5c^7

7a^3b^5c^7

4x3 = 12
a^2 x a = a^3
b^3 x b^2 = b^5
c^4 x c^ 3 = c^7

Explanation

4x3 = 12
a^2 x a = a^3
b^3 x b^2 = b^5
c^4 x c^ 3 = c^7

7. 4.5 x 10⁷ x 4.5 x 10³

20.25 x 10^10

9 x 10^10

20.25 x 10^21

20.25 x 10^4

4.5 x 4.5 = 20.25
add the exponents = 10^10

Explanation

4.5 x 4.5 = 20.25
add the exponents = 10^10

8. Evaluate: 3a²b

If: a=-4 and b=5

-240

240

-120

120

3 x (-4x-4) x 5

The expression 3a2b can be simplified by substituting the given values of a and b, which are -4 and 5 respectively. So, the expression becomes 3 x (-4 x -4) x 5. When we simplify this expression, we get -240. Therefore, the correct answer is -240.

Explanation

The expression 3a2b can be simplified by substituting the given values of a and b, which are -4 and 5 respectively. So, the expression becomes 3 x (-4 x -4) x 5. When we simplify this expression, we get -240. Therefore, the correct answer is -240.

9. A square has an area of 36 m².
What is the perimeter of the square?

24 meters

46 meters

36 meters

6 meters

perimeter = length of side x number of sides

Explanation

perimeter = length of side x number of sides

10. Which of the following is NOT written in scientific notation?

3.4 x 10^5

3.00 x 10^-10

2.21 x 10^3

0.0321 x 10^4

Scientific notation has the main number between 1 and 10. 0.0321 is less than 1.

Explanation

Scientific notation has the main number between 1 and 10. 0.0321 is less than 1.

11. Write as a single power.

(3²)(3³)

3^6

9^5

3^5

243

The given expression is the product of two powers with the same base, 3. When multiplying powers with the same base, we add the exponents. In this case, the exponent of 3 is 5. Therefore, the simplified expression is 3^5.

Explanation

The given expression is the product of two powers with the same base, 3. When multiplying powers with the same base, we add the exponents. In this case, the exponent of 3 is 5. Therefore, the simplified expression is 3^5.

12. Use your calculator. Round to 2 decimal places.

35.6
3.2 x 4.5

50.16

2.47

5.60

49.36

Explanation