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-BARSIC- [3]
3 years ago
9

If cosх A/2 =3/5, find the value of cos A​

Mathematics
1 answer:
nikitadnepr [17]3 years ago
5 0

Answer:

cosA = - \frac{7}{25}

Step-by-step explanation:

Using the double angle identity

cos2A = 2cos²A - 1 , then

cosA = 2cos²(\frac{A}{2} ) - 1 , that is

cosA = 2 × (\frac{3}{5} )² - 1

        = 2 × \frac{9}{25} - 1

       = \frac{18}{25} - \frac{25}{25}

       = - \frac{7}{25}

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A company makes a profit of $7 per software program and $8 per video game. The company can produce at most 90 software programs
g100num [7]

Answer:

930 dollars

Step-by-step explanation:

Let software programs = S

Video game = V

Given that a company makes a profit of $7 per software program that is, 7S and $8 per video game that is, 8V. The company can produce at most 90 software programs and at most 80 video games per week. Since the Total production cannot exceed 120 items per week.

How many items of each kind should be produced per week in order to maximize the profit?

The to get profit P

P = 7S + 8V

Since the profit on video game is higher, we will give maximum production to video game. Therefore,

P = (30 × 7) + ( 8 × 90)

P = 210 + 720

P = 930 dollars

6 0
3 years ago
Factor the following<br> n^2 + 6n
Veronika [31]

Answer:

n(n + 6)

Step-by-step explanation:

n² + 6n = n(n + 6)

4 0
3 years ago
Read 2 more answers
A dance school has 63 ballet dancers a 42% of the total number of dancers in the score ballet dancers what is the total number o
melamori03 [73]
42% of what is 63

0.42x = 63
x = 63/0.42
x = 150

There are 150 dancers in the school
3 0
3 years ago
A pair of jeans at a store in Seattle costs $220. Since the jeans are from last season, they are 15% off. Because of a Thanksgiv
Lostsunrise [7]

The total percent discount on the jeans is 35% amounting to $77

<h3>Discount</h3>

  • Cost of a pair of jean = $220

  • Discount from last season = 15%
  • Discount from Thanksgiving day = 20%

Total percentage discount = 15% + 20%

= 35%

Amount of discount = Total percentage discount × Cost of a pair of jean

= 35% × $220

= 0.35 × 220

= $77

Therefore, the total percent discount on the jeans is 35% amounting to $77

Learn more about discount:

brainly.com/question/7459025

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6 0
2 years ago
Jamie and Stella are saving money to sign up for a school trip to Washington, D.C. In order to sign up for the trip, they must p
sveticcg [70]

Answer:

  •    Part 1: 25x ≥ 600
  •    Part 2: 15y ≥ 600
  •    Part 3: y ≤ 40

Explanation:

Verbal statements must be translated into algebraic expressions, equations or inequalities.

<u>1. Money earned by Jamie washing cars for $25 each</u>

   Let x represent the number of cars Jaime washes.

  •    25x

<u>2. Money earned by Stella  making pecan pies for $15 each</u>

   Let y represent the number of pies she makes

  •    15y

<u>3. Constraint on the number of pies that Stella can make because she only has enough supplies to make 40 pies</u>.

Write an inequality using the symbol ≤, since y can take any integer value up to 40.

  •    y ≤ 40

4. First question:

Part 1: Write a constraint (an inequality) to represent how much money Jamie needs for his trip

  •    25x ≥ 600

5. Second question:

Part 2: Write a constraint (an inequality) to represent how much money Stella needs for her trip.

  •    15y ≥ 600

6. Third question

Part 3: Write a constraint (an inequality) to represent the limitations of Stella's supplies.

From step # 3

  •    y ≤ 40

7. Conclusion

You can solve the inequalities fo find whether Stella can or not afford the trip:

Solve for the inequalities that represent Stella's situation:

  •  15y ≥ 600
  •    y ≥ 600 / 15
  •    y ≥ 40
  •    From step 6: y ≤ 40

The solution set is the intersection of the two solutions:

  • y ≥ 40 ∩ y ≤ = 40 = 40.

  • Interpretation: Stella will be able to make 40 pies, which represents a revenue of $ 15 / pie × 40 pie = $ 600, so she will be able to make the trip.

6 0
3 years ago
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