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
lara [203]
2 years ago
9

Write the equation in standard form. Identity the center and radius. x² + y2 + 8x-4y-7=0

Mathematics
1 answer:
lorasvet [3.4K]2 years ago
8 0

Answer:

equation;

(x + 4) {}^{2}  + (y - 2) {}^{2}  = 27

Center (-4,2)

Radius is

3 \sqrt{3}

Step-by-step explanation:

Since the x^2 and y^2 have the same coeffiecent this will be a circle in a form of

(x - h) {}^{2}  + (y - k)  {}^{2}  =  {r}^{2}

Where (h,k) is center

r is the radius

So first we group like Terms together

{x}^{2}  + 8x  +  {y}^{2}  - 4y - 7 = 0

Add 7 to both sides

{x}^{2}  + 8x +  {y}^{2}  - 4y = 7

( {x}^{2}  + 8x) +(  {y}^{2}  - 4y) = 7

Since the orginal form of the equation of the circle has a perfect square we need to complete the square for each problem

(\frac{8}{2} ) {}^{2}  = 16

and

( - \frac{4}{2} ) {}^{2}  = 4

so we have

{x}^{2}  + 8x + 16 +  {y}^{2}  - 4y + 4y = 7 + 16 + 4

{x}^{2}  + 8x + 16  +  {y}^{2}  - 4y + 4y = 27

(x + 4) {}^{2}  +  (y  - 2) {}^{2}  = 27

To find our center, h is -4 and k is 2

so the center is (-4,2)

The radius is

\sqrt{27}  = 3 \sqrt{3}

So the radius is 3 times sqr root of 3.

You might be interested in
What percentage is 390 grams of 800 grams?
valentina_108 [34]

Answer:

390/800=48.75%

Step-by-step explanation:

4 0
2 years ago
If triangle ABC is rotated 180 degrees, reflected over the y-axis, and reflected over the X-axis, where will point A' lie?
Bumek [7]
The first one (5,-4)
5 0
3 years ago
Read 2 more answers
1 point
s2008m [1.1K]

Answer:

i do not know

Step-by-step explanation:

6 0
2 years ago
Plz help me with this
Artemon [7]

Answer:

C Is the corect answer

Step-by-step explanation:

Brcause you multiple the 4 and 8 = 38

plus 3,000 = 7483 and you dicide 7483/2

= 250r + 250

6 0
2 years ago
Find the distance between the two points in simplest radical form. (0,−7) and (−6,1)
astra-53 [7]

Answer:

10

Step-by-step explanation:

d = √(x2  -x1)² + (y2 - y1)²

√(-6 - 0)² + [1 - (-7)]²

√(-6)² + (8)²

√(36) + (64)

√100

= 10

4 0
2 years ago
Other questions:
  • Caleb wants to work as a dog walker. One client offers him $10 per day to walk his dog Puff, and wants Caleb to walk Puff every
    10·1 answer
  • Help !!!!!!!!!!<br><br> Please!!!!!!!<br><br> PLEASE!!!!!!
    9·1 answer
  • How to show how to find the answer to -3 +4 -1
    15·1 answer
  • Mustafa’s soccer team is planning a school dance as a fundraiser. The DJ charges $200 and decorations cost $100. The team decide
    11·2 answers
  • QUICK HELP PLEASE SHOW WORK THANKS
    8·2 answers
  • A = 1, b = 5, c = 4 <br> a = 2, b = 1, c = -21
    15·1 answer
  • 7.
    13·1 answer
  • Please help with simplifying​
    12·1 answer
  • Suppose a basketball team had a season of games with the following characteristics:
    8·1 answer
  • A school has 8 periods at day each of 45 minutes duration. How long would each period be ? The school has 6 periods a day? (assu
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!