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
charle [14.2K]
3 years ago
10

HELp meh with this question it very hard

Mathematics
1 answer:
Dovator [93]3 years ago
4 0

Answer:

  • AB = 7 cm

Step-by-step explanation:

<u>Use the law of cosines to find the side AB:</u>

  • AB = \sqrt{(x + 3)^2+x^2-2x(x+3)cos (60)} =
  • \sqrt{x^2+6x+9+x^2-x^2-3x}  = \sqrt{x^2+3x+9}

<u>Use the Heron's area formula next:</u>

  • A = \sqrt{s(s - a)(s-b)(s-c)}, where s- semi perimeter
  • s = 1/2[x + x + 3 + \sqrt{x^2+3x+9}) = 1/2 (2x + 3 + \sqrt{x^2+3x+9})
  • s - a = 1/2 (2x + 3 + \sqrt{x^2+3x+9} - 2x - 6) = 1/2 (\sqrt{x^2+3x+9 } - 3)
  • s - b = 1/2 (2x + 3 + \sqrt{x^2+3x+9} - 2x) = 1/2 (\sqrt{x^2+3x+9} + 3)
  • s - c = 1/2 (2x + 3 + \sqrt{x^2+3x+9} - 2\sqrt{x^2+3x+9}) = 1/2 (2x + 3 - \sqrt{x^2+3x+9})

<u>Now</u>

  • (s - a)(s - b) = 1/4 [(x²+3x+9) - 9] = 1/4 (x² + 3x)
  • s(s - c) = 1/4 [(2x + 3)² - (x² + 3x + 9)] = 1/4 (3x²+ 9x) = 3/4(x² + 3x)

<u>Next</u>

  • A² = 3/16(x² + 3x)(x² + 3x)
  • 300 = 3/16(x² + 3x)²
  • 1600 = (x² + 3x)²
  • x² + 3x = 40

<u>Substitute this into the first equation:</u>

  • AB = \sqrt{40 + 9} = 7 cm

You might be interested in
What number do we use to replace the (a) a-(-19)= -12
Lena [83]

Answer:

-31

Step-by-step explanation:

We write the equation out

a-(-19)=-12

Distribute the -1

a+19=-12

Subtract the 19 on both sides

a=-31

7 0
3 years ago
What is 17 x 5.8 SHOW YOUR WORK please send a photo of work by pressing
11Alexandr11 [23.1K]

Answer:

98.6

Step-by-step explanation:

in photo!!

3 0
1 year ago
Help me answer this question please
Stella [2.4K]

ANSWER

{f}^{ - 1}  =\pm \sqrt{x + 1}

EXPLANATION

The given function is

f(x) =  {x}^{2}  - 1

Let

y =  {x}^{2}  - 1

Interchange x and y to get:

x=  {y}^{2}  - 1

Solve for y,

x + 1 =  {y}^{2}

Take square root of both sides to get,

\pm \sqrt{x + 1}  = y

This is the same as:

y =  \pm \sqrt{x + 1}

Therefore the inverse is

{f}^{ - 1}  =\pm \sqrt{x + 1}

3 0
3 years ago
chantal volunteered to bring 1 gallon of freshly squeezed orange juice to a picnic.the local grocery store sells 4-pound bags of
pochemuha
(128 oz) * (2 oranges)/(5 oz) * (1 bag)/(11.5 oranges) * $3.49/bag ≈ $15.54

Note that we have assumed 11.5 oranges per bag, and that partial bags are available.

If Chantal must buy whole bags of oranges, 5 bags will be needed and the cost will be $17.45.
6 0
3 years ago
​% off. Find the sale price of each washing machine. Use pencil and paper. Explain why KareemKareem should buy the first washing
ExtremeBDS [4]
Not all info is here. what is the original cost and %off?
8 0
3 years ago
Other questions:
  • What is the circumference of circle p?<br> Express your answer in terms of pi. <br><br> AB=20 cm
    12·1 answer
  • a varies directly as b and inversely as the square of c. If a = 197 when b = 5 and c = 5, find a if b = 3 and c = 3
    15·1 answer
  • Would someone take the time and help me
    10·1 answer
  • Suppose the tortoise travels for 12 seconds. Explain how you could find the distance the tortoise travels
    13·1 answer
  • Which table represents the same proportional relationship as the equation y = 36 x?
    5·2 answers
  • What is the value of 14 please my h.w is till Friday I'm freaking out
    9·1 answer
  • Given: A(-4,1), B (6, 1), C (-2, -3), D (4, -3), E (5, 4) and the center O (1, 1); use 3.14 for
    14·1 answer
  • A shopkeeper fixed the marked price of his radio to make a profit of 30 percentage. allowing rs 30 as a discount then the profit
    9·1 answer
  • I need help solving this
    6·1 answer
  • What is gross income?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!