Question

What is the general form of the equation of a circle with its center at (-2, 1) and passing through (-4, 1)?

Answer 1

Answer:

( x + 2 )² + ( y - 1 )² = r²

( - 4 + 2 )² + ( 1 - 1 )² = r²

4 = r², than we will plug in to a formula:

( x + 2 )² + ( y - 1 )² = 4

x² + 4 x + 4 + y² - 2 y +1 = 4

x² + y² + 4 x - 2 y + 1 = 0

Answer: B )