202k views
2 votes
What is the radius of a circle with the equation x2 + y2 – 14x + 10y = 250? A) 9 units B) 12 units C) 15 units D) 18 units

User Nida Amin
by
8.0k points

1 Answer

2 votes

Answer:

D

Explanation:

To find the radius of the circle with equation x2 + y2 – 14x + 10y = 250, convert the equation into vertex-form (x - h)² + (y-k)² = r². Convert by completing the square for x² - 14x and y² + 10y.

Complete the square by dividing each term -14x and 10y in two. Then square each.

-14/2 = -7 and -7² = 49

10/2 = 5 and 5² = 25

The equation becomes x² - 14x + 49 + y² + 10y + 25 = 250 + 49 + 25.

We simplify the equation into (x-7)² + (y + 5)² = 324.

324 is the value of radius squared. Take the square root to find the radius.

√324 = 18

The radius is 18 units.

User Wilcroft
by
8.7k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.