Answered

Discover a wealth of knowledge at Westonci.ca, where experts provide answers to your most pressing questions. Experience the ease of finding accurate answers to your questions from a knowledgeable community of professionals. Our platform offers a seamless experience for finding reliable answers from a network of knowledgeable professionals.

What is the radius of a circle whose equation is x2+y2+8x-6y+21=0?
O 2 units
O 3 units
4 units
ОО
O 5 units

Sagot :

razz25

Answer:

the correct answe is 2 cm

Step-by-step explanation:

if u need process I have...

oladayoademosu

The radius of the circle whose equation is x² + y² + 8x - 6y + 21 = 0 is 2 units

Radius of a circle

Since the equation of the circle is x² + y² + 8x - 6y + 21 = 0, to find the radius, we complete the square in the terms x and y and convert it to the form (x - a)² + (y - b)² = r²  (1) which is the standard equation of a circle.

So, x² + y² + 8x - 6y + 21 = 0

x² + 8x + y² - 6y + 21 = 0

x² + 8x + (8/2)² - (8/2)² + y² - 6y + (-6/2)²  + (-6/2)² + 21 = 0

x² + 8x + 4² - 4² + y² - 6y + (-3)²  - (-3)² + 21 = 0

(x + 4)² - 4² + (y - 3)²  - (-3)² + 21 = 0

(x + 4)² - 16 + (y - 3)²  - 9 + 21 = 0

(x + 4)² + (y - 3)² - 16 - 9 + 21 = 0

(x + 4)² + (y - 3)² - 4 = 0

(x + 4)² + (y - 3)² = 4  (2)

Comapring (1) and (2), r² = 4

So, r = √4

r = 2

So, the radius of the circle whose equation is x² + y² + 8x - 6y + 21 = 0 is 2 units

Learn more about equation of a circle here:

https://brainly.com/question/24810873

Thank you for visiting. Our goal is to provide the most accurate answers for all your informational needs. Come back soon. Thank you for your visit. We're committed to providing you with the best information available. Return anytime for more. Thank you for choosing Westonci.ca as your information source. We look forward to your next visit.