1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oliga [24]
3 years ago
11

Use the Law of Cosines to find angle round to the nearest tenth if necessary).

Mathematics
1 answer:
ad-work [718]3 years ago
7 0

Answer:

Step-by-step explanation:

3a)

find side HP  , let's set side HP = c in the law of cosines formula

then

c = sq rt [ 23^2 + 12^2 - 2*12*23*cos(117) ]

c = sq rt [ 529 + 144 - (-250.6027559) ]

c = sq rt [ 673 + 250.6027559 ]

c = sq rt [ 923.602755 ]

c = 30.39

then

HP = 30.4  ( rounded to nearest 10th )

3b)

let PR = c, then law of cosines is (we need angle Q also 180=24+97+Q is 59°

c = sq rt [ 9^2 + 22^2 - 2*9*22*cos(59) ]

c = sq rt [ 81 + 484 -396*0.5150380 ]

c = sq rt [ 565 - 203.955 ]

c = sq rt [ 391.04495]

c = 19.7748

PR = 19.8  ( rounded to nearest 10th )

3c)

they want us to find ∠B,   in the formula for cosines ∠B is really ∠C, it's a bit confusing.. I'm sure they did that on purpose to mess people up.  Kind of underhanded  :/    Tell the teacher that you're "appalled" at the deviousness of the test  :/   stage a protest against math that teaches treachery  :P  storm the principals/ dean's  office with paper airplanes and pictures of anime   :DDD  okay back to math.

a=28

b=17

c=15

since we want angle B then the formula looks like

B= arcCos ( a^2 + c^2 - b^2 / 2*a*c)  so we'll avoid messing up the which side is which ... by setting up the formula this way   .. got it?

B = arcCos [28^2 + 15^2 - 17^2 / 2*28*15]

B = arcCos[784 + 225 - 289 /840 ]

B = arcCos[720/ 840]

B = arcCos[0.85714285]

B = 31.0027 °

that it came out so close to an integer I'm pretty sure it's right

∠B = 31 .0 °  ( rounded to the nearest 10th )

3d)

find ∠A

set it up carefully again, they are asking us to move the variable around again

a = 18

b= 28

c= 12

then the formula looks like

∠A = arcCos[ b^2 + c^23 - a^2 / 2*b*c ]

∠A = arcCos[28^2 + 12^2 - 18^2 /2*28*12 ]

∠A = arcCos[784 + 144 -324 / 672 ]

∠A = arcCos[604/672]

∠A = arcCos[0.8988095]

∠A =25.99797 °

∠A =26.0 °  ( rounded to nearest 10th)

You might be interested in
Need by tomorrow please help
nikklg [1K]
1    - 9
2   -28 
3    54
4    -100
5   -60
6     0
7   49
8   -135
9    -96
10   300
11    0
12    192
6 0
3 years ago
Read 2 more answers
How do I find the volume of a cube
Alenkasestr [34]

Answer: To find the volume of a cube, use the formula V=lwh, or Volume equals length times width times height.

5 0
3 years ago
Read 2 more answers
Hurry pls!!! PLS ANSWER THE ATTACHMENT BELOW!!!
seraphim [82]

Answer:

58

Step-by-step explanation:

You just have to replace the value of n with 4.

C(n) = 46 + 3n

C(4) = 46 + 3(4)

       = 46 + 12

       = 58

4 0
2 years ago
Read 2 more answers
22
dalvyx [7]

The first digit may be 1 or 8.

The second digit may be 1, 2, 4, 8.

The third digit may be 1, 3, 5, 7, 9.

There are 2\times4\times5=40\:variants

The probability that this is the correct code is \frac{1}{40}

8 0
2 years ago
A sequence can be generated ny using (look at image below)? someone please help:)
mixer [17]

Answer:

6, 24, 96, 384

Step-by-step explanation:

a₁ = 6

a₂ = 4 x a₁ = 4 x 6 = 24

a₃ = 4 x a₂ = 4 x 24 = 96

a₄ = 4 x a₃ = 4 x 96 = 384

8 0
3 years ago
Other questions:
  • Is 40% less than or greater than 1/4
    8·1 answer
  • What is the distance between (-5,-5) and (-9,-2)
    15·1 answer
  • The graph shows y as a function of x: In which segment is the function constant?
    6·2 answers
  • Find an exact value. <br><br> cosine of negative seven pi divided by twelve
    11·1 answer
  • suppose you to multiply a whole number greater than 1 by the fraction3/5. will the product be greater than, less than, or equal
    10·1 answer
  • HELP! A circle is inscribed in a square. A point N in the square is chosen at random. What is the probability that N lies in the
    8·1 answer
  • 23.21 to the nearest hundredth​
    10·1 answer
  • Pls help me find v,w,x,y, and z pls help me I will mark u brainlest
    9·1 answer
  • Find the constant of proportionality
    11·1 answer
  • Write an equation in standard form of the line passing through the points (12, 3) and (-3, 8).
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!