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
miss Akunina [59]
3 years ago
11

In a triangle ABC, AB = 7, AC = 8, BC = 3, what is cos(A)?

Mathematics
1 answer:
kotegsom [21]3 years ago
6 0
Use the cosine rule.
c=AB=7
b=AC=8
a=BC=3
a^2=b^2+c^2-2bc(cos(A)) 
=>
cos(A)=(b^2+c^2-a^2)/(2bc)
=(7^2+8^2-3^2)/(2*7*8)
=13/14
=0.9286
You might be interested in
What are the values of x and y given that ABCD ≅ EFGH?
Margarita [4]

Answer:

x = 7

y = 8

Step-by-step explanation:

Since the shapes are similar then <B = <F and <A = <E

<B = <F so

10x + 65 = 135 subtract 65 from both sides

10x = 70 divide both sides by 10

x = 7

<A = <E so

4y - 4 = 28 add 4 to both sides

4y = 32 divide both sides by 4

y = 8

7 0
3 years ago
Help!!! Please please I don’t know this at all
Lesechka [4]

Answer:

X+y=180, Y=Z, X+Z=180

Step-by-step explanation:

Hope this helps, i remember doing this lesson.

3 0
3 years ago
Please help me, im desperate
Arada [10]

Answer: C. “BEC”

Step-by-step explanation:

5 0
2 years ago
A fine fabric was selling for $10.50 per half yard. Joni bought 2 1/3 yards. How much did he spend? Brainliest for correct answe
Alinara [238K]

Answer:

45.5

Step-by-step explanation:

First you would find 1/3 third of 10.50 and it is 3.5, you would then do 10.50 x 4 since it said 10.50 per half a yard, so you would do times 4 and you would get 42, you would then add 42 + 3.5 which equals 45.5.

8 0
3 years ago
Read 2 more answers
What does 12 ÷3/4 equal? ​
djyliett [7]

Answer:

16.

Hope this helps, have a great day/night!

5 0
3 years ago
Other questions:
  • Is f(x)=x^2-3x+2 even function
    11·1 answer
  • A computer system password requires five characters, all lowercase letters (remember there are 26 letters), and all the letters
    15·1 answer
  • How do you do -2z&lt;-6
    10·1 answer
  • line j has an equation of y=-x+8. line k includes the point (1,-3) and is perpendicular to line j. what is the equation of line
    5·1 answer
  • Which expression is equivalent to -1/3(6x+15)-3
    5·2 answers
  • What is one way to remember that one-fourth is the same as 0.25? Next, explain how 1/2 is the same as 0.5.
    7·1 answer
  • NEED HELP!! 30 POINTS! HAS TO BE CORRECT AND NEED THE ANSWER NOOW!
    13·1 answer
  • In circle O, if LP congruent LK, find the measurement of the major arc PNK. A. 112 B.156 C.224 D.248
    14·2 answers
  • HELP !!!!! the graph below shows arianas pay as a painter how much does ariana charge per painting
    9·2 answers
  • What does statement maen
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!