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1 vote
What are the center and radius of a circle defined by the equation x^2+y^2- 6x+ 8y+ 21=0?

A. Center (3,-4); radius 4
B. Center (3,-4); radius 2
C. Center (-3,4); radius 2
D. Center (-3,4); radius 4

PLEASE HELP ME QUICK!

2 Answers

6 votes

Answer:

It is B, Thank me later

Step-by-step explanation:


User Jannina
by
6.3k points
6 votes
You have to complete the square. When you do this you get an equation that looks like this: (x-3)^2 + (y+4)^2 = 4. So your center is (3, -4) and your radius is 2. That looks like B to me!!!
User Lefloh
by
7.7k points
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