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
Dima020 [189]
4 years ago
13

What is the radius of a circle whose equation is x2 + y2 + 8x – 6y + 21 = 0? units

Mathematics
2 answers:
Artemon [7]4 years ago
5 0

Answer:

2 units

Step-by-step explanation:

on edg

weqwewe [10]4 years ago
4 0

To answer this, use "completing the square."

x2 + y2 + 8x – 6y + 21 = 0 becomes

x^2 + 8x + 16 - 16 + y^2 - 6y + 9 - 9 + 21 = 0

 (x + 4)^2       -16     + (y - 3)^2     + 12 = 0

or   (x + 4)^2      + (y - 3)^2   = 4

Since 4 = r^2, r = 2 units, and the center is at (-4, 3)

You might be interested in
Jus need help with exercise 3 ONLY
WARRIOR [948]

Let us start with something we know is true.

5 > 3

That reads as 5 is greater than 3. Anyone will tell you that that is a true statement.

But what happens when you multiply this result by - 10

5 * -10 > 3 * - 10

- 50 >  -  30 is that true? If you are not sure, think it terms of money. Which would you rather be

owing 50 dollars to some or owing 30 dollars to someone? Of course if you are careful with money you would likely say neither. But this is math so you have to choose.

You likely would have to say you would want to owe 30 dollars. That makes  - 30 larger than - 50. So a true statement has now become a false one. Check with me if you don't understand. I'd like to know if you accept my explanation.

3 0
3 years ago
The sum of three consecutive multiples of 2 is 18 .
weeeeeb [17]

Answer:

<em>consecutive </em><em>mult</em><em>iple</em><em> </em><em>of</em><em> </em><em>2</em><em> </em><em>is</em><em> </em><em>2</em><em>,</em><em>4</em><em>,</em><em>6</em><em> </em>

<em>this</em><em> </em><em>sum</em><em> </em><em>is</em><em> </em><em>2</em><em>+</em><em>4</em><em>+</em><em>6</em><em> </em><em>is</em><em> </em><em>1</em><em>2</em>

5 0
3 years ago
Need help with these. 11th grade algebra 2 class. thanks ​
OlgaM077 [116]

15) x=31/10
16)x=2
17)x=16/3
18)x=-2
19)2.5 hours
20) 32 hours
3 0
3 years ago
Evan paid $60.54 for 3 notebooks and a calculator. If the calculator costs $45.87, how much does each notebook cost? Write a two
Aleonysh [2.5K]

Answer:   4.89$

Step-by-step explanation:

60.54 is starting amount then subtract 45.87 left with 14.67 then divide by 3 get 4.89

60.54-45.87=14.67

14.67/3=4.89

7 0
3 years ago
Read 2 more answers
Last year, Pattersonville had a population of 40,500 people . The census indicated that the population of the town has been decr
AleksandrR [38]

Answer:

34175 people will live in Pattersonville 8 years from now

Step-by-step explanation:

Initial population of Pattersonville =40,500

We are given that The census indicated that the population of the town has been decreasing by 2.1% per year .

Now we are supposed to find If this trend continues , approximately how many people will live in Pattersonville 8 years from now

Formula : N(t)=N_0(1-r)^t

Where N(t)= Population after t years

N_0= Initial population

r = rate of decrease = 2.1 %=0.021

t = 8 years

Substitute the values in the formula :

So,N(8)=40500(1-0.021)^8

N(8)=34175.63223

So, 34175 people will live in Pattersonville 8 years from now

7 0
3 years ago
Other questions:
  • Please help. I don't understand where to start with this one. If the slope of a strictly decreasing function at the point (a, b)
    12·2 answers
  • Which interval is the solution set to 0.35x – 4.8 &lt; 5.2 – 0.9x
    7·2 answers
  • X2-5x-14=0<br> A=1 B=-5C=-14
    5·2 answers
  • Johnny did some work for his grandpa. He worked for 7 hours on Friday and 6 hours on Saturday. His grandpa paid him $91 for the
    8·1 answer
  • Which of the following is a solution of x2 + 5x = −2? (2 points) 5 plus or minus the square root of 33 divided by two. 5 plus or
    6·1 answer
  • How many possible outcomes are there for this event?
    7·1 answer
  • I just need just a little help and I will just answer it
    7·2 answers
  • What is relationship between the number of stitches and the length
    7·2 answers
  • Plot two points that are 8 units from Point B and also share the same x-coordinate as Point B. y​
    12·2 answers
  • ALGEBRAIC EXPRESSIONS AND EQUATIONS
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!