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
yaroslaw [1]
3 years ago
8

Given that Triangle ABC such thata=8cm, b=7cm and c=9cmtem and c= 9cm find Cos B​

Mathematics
1 answer:
charle [14.2K]3 years ago
4 0

Answer:

We use cosine rule also called cosine law which states

c^2=a^2+b^2-2abcosC

given

a=8cm, b=7cm, c=9cm cos C?

9^2=8^+7^2-2*8*7 cos C

expand

81=64+49-112 cos C

like terms together

81-113=-112 cos C

-32=-112cos C

multiply both sides by -1

32=112cos C

divide both sides by 112

32/112=cos C

cosC=0.2857

find cos inverse of 0.2857

angle C= 73.40

You might be interested in
The formula for the volume of a sphere is V= 4/3 pi r cubed. what is the formula solved for r
Reil [10]
V=4/3π r^3

(3/4)V=π r^3

3V/4π = r^3

third root√(3V/4π)

<span><span>Hope this helps!
</span>and May the Force Be With You
</span><span>
-Jabba</span>
6 0
3 years ago
Read 2 more answers
The smiths have two children. The sum of their ages is 23. The produce of their ages is 132. How old are the children?
kolezko [41]

For this case we propose a system of equations:

x: Let the variable representing the age of the first child of the Smiths

y: Let the variable representing the age of the second child of the Smiths

According to the data of the statement we have to:

x + y = 23\\x * y = 132

From the first equation we have to:

x = 23-y

We substitute in the second equation:

(23-y) * y = 132\\23y-y ^ 2 = 132\\y ^ 2-23y + 132 = 0

We find the solutions by factoring:

We look for two numbers that, when multiplied, result in 132 and when added, result in 23. These numbers are 11 and 12.

Thus, we have that the factorized equation is:

(y-11) (y-12) = 0

Thus, the solutions are:y_ {1} = 11\\y_ {2} = 12

So, we can take any of the solutions:

With y = 11

Thenx = 23-11 = 12

Therefore, the ages of the children are 11 and 12 respectively.

Answer:

 The ages of the children are 11 and 12 respectively.

6 0
3 years ago
In the morning, Alan drove 100 miles at the rate of 60 miles per hour; in the afternoon, he drove another 100 miles at the rate
klio [65]
300 Is the correct answer
5 0
3 years ago
Jason can make 7 origami cranes in 10 minutes. How many minutes will it take to make 1505 origami cranes
Angelina_Jolie [31]

Answer:

The unit rate = 7/10 cranes per minute

Step-by-step explanation:

So, the number of minutes would it would take Kenny to fold 1505 cranes is  

10/7 x 1505 = 2150 minutes

2150/60 = 35 5/6 hours

8 0
2 years ago
Read 2 more answers
Use the drop-down menus to answer the questions,
Mashcka [7]

Step-by-step explanation:

survey a specific amount of students and ask then if they spend les that 2 hours a night of studying or 2 or more hours a night studying.

3 0
3 years ago
Read 2 more answers
Other questions:
  • Translate the sentence into an inequality. <br> Twice w is greater than 24.
    7·1 answer
  • The amount of money that college students spend on rent each rent month is usually between 300 and 600.However there are a few s
    13·1 answer
  • Solve the formula A=10+ry. solve for y
    8·2 answers
  • Compare 2/3 and 2/5 right one or both of the fractions so they have the common denominator use greater than less than or equal t
    6·1 answer
  • What property is this? <br> (10b+12b)+7b=(12b+10b)+7b
    10·1 answer
  • Identify the transformations y = |x| ‐ 6
    12·1 answer
  • Which graph represents viable values for y = 2x, where x is the number of pounds of rice scooped and purchased from a bulk bin a
    8·1 answer
  • Find the 64th term of the arithmetic sequence 29, 38, 47, ...
    5·1 answer
  • Can someone plz help me
    8·1 answer
  • Sam bought an $85.00 jacket for 40% off of the regular price. How much
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!