Question
A circle has center C at (1,1) and radius 2. Which of the following is an equation of this circle?
- (\(x\)+1)2+(\(y\)+1)2=2
- (\(x\)+1)2+(\(y\)+1)2=4
- (\(x\)-1)2+(\(y\)-1)2=2
- (\(x\)-1)2+(\(y\)-1)2=4
Answer/Explanation
Ans: D
Question
\(x\)2-10\(x\)+\(y\)2+6\(y\)=2
The graph in the \(xy\)-plane of the equation above is a circle. What are the coordinates of the center of the circle?
- (-5,-3)
- (-5,3)
- (5,-3)
- (5,3)
Answer/Explanation
Ans: C
Question
\(x\)2-6\(x\)+\(y\)2-8\(y\)=0
The graph of the given equation in the \(xy\)-plane is a circle. What is the radius of the circle?
- 2
- 3
- 4
- 5
Answer/Explanation
Ans: D
Question
In the \(xy\)-plane, a circle with radius 2 has center (0,0). Which of the following is a equation of the circle?
- \(x\)2+\(y\)2=2
- \(x\)2+\(y\)2=4
- \(x\)2-\(y\)2=2
- \(x\)2-\(y\)2=4
Answer/Explanation
Ans: B
Question
In the \(xy\)-plane, the points (-3, 10) and (3, 10) are endpoints of the diameter of a circle. Which equation represents this circle?
- \(x\)2+(\(y\)-10)2=9
- (\(x\)+3)2+\(y\)2=36
- (\(x\)+3)2+(\(y\)-10)2=9
- (\(x\)+3)2+(\(y\)-10)2=36
Answer/Explanation
Ans: A
Question
\((x + 3)^{2} + (y – 7)^{2} = 100\)
In the \(xy\)-plane, the graph of the given equation is a circle. Which point \((x, y)\) lies on the circle?
- (3, -4)
- (3, -1)
- (3, 1)
- (3, 4)
Answer/Explanation
Ans: B
Question
\(x^2 – 8x + y^2 – 10y = 40\)
In the \(xy\)-plane, the graph of the given equation is a circle. What is the radius of this circle?
Answer/Explanation
Ans: 9