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
Stella [2.4K]
3 years ago
9

Answer the following questions about the sphere whose equation is given by x2+y2+z2−8x+4y=−4. 1. Find the radius of the sphere.

Radius: ????= 2. Find the center of the sphere. Write the center as a point (????,????,c) where ????, ????, and c are numbers. Center:
Mathematics
1 answer:
Anna [14]3 years ago
8 0

Answer:

we have (a,b,c)=(4,-2,0) and R=4 (radius)

Step-by-step explanation:

since

x²+y²+z²−8x+4y=−4

we have to complete the squares to finish with a equation of the form

(x-a)²+(y-b)²+(z-c)²=R²

that is the equation of a sphere of radius R and centre in (a,b,c)

thus

x²+y²+z²−8x+4y=−4

x²+y²+z²−8x+4y +4 = 0

x²+y²+z²−8x+4y +4 +16-16 =0

(x²−8x + 16) + (y² + 4y + 4 ) + (z²) -16 = 0

(x-4)² + (y+2)² + z² = 16

(x-4)² + (y-(-2))² + (z-0)² = 4²

thus we have a=4 , b= -2 , c= 0 and R=4

You might be interested in
50 points if you can help me??!!!!
Sedaia [141]

Answer:

The answer is C. An absolute value will never have a negative in it.

Step-by-step explanation:

3 0
3 years ago
Read 2 more answers
$7230 for 3.25% in 12 years
IceJOKER [234]

$2,819.70 is the answer

You multiply .0325×12×72.30

6 0
3 years ago
One-Half of a number increased by 6 is less than 34
Vlada [557]

Answer: ½ x + 6 < 34 ; x < 56

Step-by-step explanation:

  1. Subtract 6 on both sides. ½ x < 28.
  2. Divide ½ on both sides. x < 56.
3 0
3 years ago
A 26 foot ladder is set against the side of a house so that it reaches up 24 feet. If Mila grabs the ladder at its base and pull
olasank [31]

Answer:

13.9 ft

Step-by-step explanation:

4 0
2 years ago
How to make 105% into a fraction?
riadik2000 [5.3K]
Percent measn parts out of 100
105%=105/100=21/20
3 0
3 years ago
Other questions:
  • You read 50 pages in an hour your sister reads 40 pages in an hour how many more pages did you read than your sister reads in 1/
    6·1 answer
  • What is the arc measure of DBC in<br> degrees?
    10·1 answer
  • The surface area of a square pyramid is found using the formula SA=b^2+2bh, where b is the length of the base and h is the heigh
    13·1 answer
  • Help help help helpn
    11·1 answer
  • Graph the function f(x) = x2 + 5x − 6 / x + 1 showing all the key features.
    13·1 answer
  • Keith needs to drive a total of 18 miles. So far, he has driven 9.4 miles. How many more miles must Keith drive?
    9·2 answers
  • What is the general formula of a quadratic equation​
    13·2 answers
  • Please asap maths homework
    11·1 answer
  • Write an equation that represents the line.<br> Use exact numbers.
    7·1 answer
  • Determine the approximate value of angle A​
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!