9th Grade Algebra 2 - Chapter 1, Lessons 1: Expressions and Formulas (tbc)

GEOMETRY: The formula for the area A of a circle with diameter d is A = π(d/2)² represent the area of the circle. Write an expression to represent the area of the circle.

π(y + 5/2)²

w = 6, x = 0.4, y = 1/2, and z = -3 5x + 2z

-4

w = 6, x = 0.4, y = 1/2, and z = -3 5xw/z

-4

w = 6, x = 0.4, y = 1/2, and z = -3 z(x + 1)

-4.2

16(9 - 22)/4

-52

1/5 - 20(81 ÷ 9)/25

-7

w = 6, x = 0.4, y = 1/2, and z = -3 2z - 15x/3y

-8

if x = 4, y = -2, and z = 6 z - x + y

0

7 - 20 ÷ 5

3

w = 6, x = 0.4, y = 1/2, and z = -3 w + x + z

3.4

(6 + 7)2 - 1

25

12(52 ÷ 2²)/6 - 2/3

25 1/

3(8 + 3) - 4

29

1/3(4 - 7²)

-15

Find the value of abᴺ if n = 3, a = 2000, and b = -1/5.

-16

[6 - (12 - 8)²] ÷ 5

-2

if x = 4, y = -2, and z = 6 x + (y - 1)³

-23

BANKING: Simple interest is calculated using the formula I = prt, where p represents the principal in dollars, r represents the annual interest rate, and t represents the time in years. Find the simple interest I given each of the following values. p = $31,000, r = 2 1/2%, t = 18 months

$1162.50

BANKING: Simple interest is calculated using the formula I = prt, where p represents the principal in dollars, r represents the annual interest rate, and t represents the time in years. Find the simple interest I given each of the following values. p = $5000, r = 3.75%, t = 10 years

$1875

BANKING: Simple interest is calculated using the formula I = prt, where p represents the principal in dollars, r represents the annual interest rate, and t represents the time in years. Find the simple interest I given each of the following values. p = $1800, r = 6%, t = 4 years

$432

1/2[9 + 5(-3)]

-3

10 − [5 + 9(4)]

-31

-2(3² + 8)

-34

[9 + 3(5 - 7] ÷ 3

1

w = 6, x = 0.4, y = 1/2, and z = -3 (5 - w)² + x

1.4

[38 − (8 − 3)] ÷ 3

11

17(2 + 26)/4

119

12 + {10 ÷ [11 − 3(2)]}

14

OPEN ENDED: Give an example of an expression where subtraction is performed before division and the symbols ( ), [ ], or { } are not used.

14 - 4/5

0.3(1.5 + 24) ÷ 0.5

15.3

45(4 + 32)/10

162

if x = 4, y = -2, and z = 6 x + [3(y + z) - y]

18

2 + 8(5) ÷ 2 − 3

19

w = 6, x = 0.4, y = 1/2, and z = -3 w + 12 ÷ z

2

w = 6, x = 0.4, y = 1/2, and z = -3 1/y + 1/w

2 1/6

1.6(0.7 + 3.3) ÷ 2.5

2.56

18 + 6 ÷ 3

20

14 × 2 - 5

23

MEDICINE: Suppose a patient must take a blood pressure medication that is dispensed in 125-milligram tablets. The dosage is 15 milligrams per kilogram of body weight and is given every 8 hours. If the patient weighs 25 kilograms, how many tablets would be needed for a 30-day supply? Use the formula n = 24d ÷ [8(b × 15 ÷ 125)], where n is the number of tablets, d is the number of days the supply should last, and b is the body weight of the patient in kilograms.

30

NURSING: Determine the IV flow rate for the patient described at the beginning of the lesson by finding the value of 1500 × 15/12 × 60.

31.25 drops per min

w = 6, x = 0.4, y = 1/2, and z = -3 (x - y)² - 2wz

36.01

w = 6, x = 0.4, y = 1/2, and z = -3 w(8 - y)

45

4 + 64 ÷ (8 × 4) ÷ 2

5

w = 6, x = 0.4, y = 1/2, and z = -3 w - 3x + y

5.3

2(6² - 9)

54

10 - 8 ÷ 2

6

1 - {30 ÷ [7 + 3(−4)]}

7

8(3 + 6)

72

w = 6, x = 0.4, y = 1/2, and z = -3 z⁴ - w

75

BICYCLING: The amount of pollutants saved by riding a bicycle rather than driving a car is calculated by adding the organic gases, carbon monoxide, and nitrous oxides emitted. To find the pounds of pollutants created by starting a typical car 10 times and driving it for 50 miles, find the value of the expression (52.84 × 10) + (5.955 × 50)/454.

About 1.8 pounds

Describe how you would evaluate the expression a b[(c + d) ÷ e] given values for a, b, c, d, and e.

First, find the sum of c and d. Divide this sum by e. Multiply the quotient by b. Finally, add a.

Determine which expression below represents the amount of change someone would receive from a $50 bill if they purchased 2 children's tickets at $4.25 each and 3 adult tickets at $7 each at a movie theater. Explain. a. 50 - 2 × 4.25 + 3 × 7 b. 50 − (2 × 4.25 + 3 × 7) c. (50 − 2 × 4.25) + 3 × 7 d. 50 − (2 × 4.25) + (3 × 7)

b; the sum of the cost of adult and children tickets should be subtracted from 50. Therefore, parentheses need to be inserted around this sum to insure that this addition is done before subtraction.