SOLUTION: Give the center of the circle with the equation x^2 + 2x + y^2 + 22 = 0 i came up with (-1, 5) from the book. the other answers are (2, 4) (1, 5) (-2, 4) am i right?

Algebra ->  Linear-equations -> SOLUTION: Give the center of the circle with the equation x^2 + 2x + y^2 + 22 = 0 i came up with (-1, 5) from the book. the other answers are (2, 4) (1, 5) (-2, 4) am i right?      Log On


   

Question 98282: Give the center of the circle with the equation x^2 + 2x + y^2 + 22 = 0
i came up with (-1, 5) from the book. the other answers are (2, 4) (1, 5) (-2, 4) am i right?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+%2B+2x+%2B+y%5E2+%2B+22+=+0 Start with the given equation


x%5E2+%2B+2x+%2B+y%5E2=+-22 Subtract 22 from both sides


Take half of 2 to get 1. Now square 1 to get 1.


x%5E2+%2B+2x+%2B1%2B+y%5E2=+-22%2B1 Add the result 1 to both sides


x%5E2+%2B+2x+%2B1%2B+y%5E2=+-21 Combine like terms



Here's where we run into problems. The right side number represents the radius of the circle. However, a negative number does not work for the radius (a length doesn't make sense). So check your problem again and make sure you entered your problem correctly.