Which of the following circles lie completely within the fourth quadrant?Check all that apply.A.(x - 5)2 + (y + 5)2 = 9B.(x - 9)2 + (y + 9)2 = 16C.(x - 12)2 + (y + 0)2 = 72D.(x - 2)2 + (y + 7)2 = 64
Question
Which of the following circles lie completely within the fourth quadrant?Check all that apply.A.(x - 5)2 + (y + 5)2 = 9B.(x - 9)2 + (y + 9)2 = 16C.(x - 12)2 + (y + 0)2 = 72D.(x - 2)2 + (y + 7)2 = 64
Solution
The equation of a circle is given by (x - h)² + (y - k)² = r², where (h, k) is the center of the circle and r is the radius.
The fourth quadrant is where x > 0 and y < 0.
Let's check each circle:
A. (x - 5)² + (y + 5)² = 9 The center is at (5, -5) and the radius is √9 = 3. The circle extends 3 units in all directions from the center, so it extends to x = 5 - 3 = 2 and y = -5 - 3 = -8. Both of these are in the fourth quadrant, so circle A is completely within the fourth quadrant.
B. (x - 9)² + (y + 9)² = 16 The center is at (9, -9) and the radius is √16 = 4. The circle extends to x = 9 - 4 = 5 and y = -9 - 4 = -13. Both of these are in the fourth quadrant, so circle B is completely within the fourth quadrant.
C. (x - 12)² + (y + 0)² = 72 The center is at (12, 0) and the radius is √72 = 8.48 (approximately). The circle extends to x = 12 - 8.48 = 3.52 and y = 0 - 8.48 = -8.48. The x-coordinate is in the fourth quadrant, but the y-coordinate is not, so circle C is not completely within the fourth quadrant.
D. (x - 2)² + (y + 7)² = 64 The center is at (2, -7) and the radius is √64 = 8. The circle extends to x = 2 - 8 = -6 and y = -7 - 8 = -15. The x-coordinate is not in the fourth quadrant, so circle D is not completely within the fourth quadrant.
So, the circles that lie completely within the fourth quadrant are A and B.
Similar Questions
Which of the following circles have their centers in the second quadrant?Check all that apply.A.(x - 5)2 + (y + 5)2 = 9B.(x + 3)2 + (y - 2)2 = 8C.(x + 12)2 + (y - 9)2 = 19D.(x - 2)2 + (y + 7)2 = 64SUBMITarrow_backPREVIOUS
Which of the following circles have their centers on the y-axis?Check all that apply.A.(x - 0)2 + (y + 5)2 = 74B.(x - 0)2 + (y - 0)2 = 44C.(x - 4)2 + (y - 0)2 = 22D.(x + 1)2 + (y - 7)2 = 16SUBMITarrow_backPREVIOUS
Which of the following circles have their centers on the x-axis?Check all that apply.
Which of the following points lies outside the circle with center (0,0) and radius 5 ?A.(4.1, 1)B.(4, 2)C.(3.8, 3)D.(2, 5)
Write the equation of a circle whose center is (-9, -8) and which has a radius of 5.A. left parenthesis x plus 9 right parenthesis squared plus left parenthesis y plus 8 right parenthesis squared equals 10B. left parenthesis x minus 9 right parenthesis squared plus left parenthesis y minus 8 right parenthesis squared equals 25C. left parenthesis x plus 9 right parenthesis squared plus left parenthesis y plus 8 right parenthesis squared equals 5D. left parenthesis x plus 9 right parenthesis squared plus left parenthesis y plus 8 right parenthesis squared equals 25
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.