Multiple Choice Question (MCQ)
The equation of a circle in the xyplane is shown here:
x^2 + y^2 + 6x – 4y = –9
What is the radius of the circle?

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1

✓
2

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3

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4
The equation of a circle in the xyplane is shown here:
x^2 + y^2 + 6x – 4y = –9
What is the radius of the circle?
1
2
3
4
Convert the equation to the standard circle equation
(x – h)^2 + (y – k)^2 = r^2
in which r is the radius of the circle.
x^2+y^2+6x4y=9
x^2+6x+9+y^24y+2=9+9+4
(x+3)^2+(y2)^2=2^2
Therefore the radius of the circle is 2
B is correct choice