Engineering Board Exam Reviewer · Circles · easy
Find the area of the circle x2+y2+8x-6y=0.
- 10 π 31.42
- 5 π 15.71
- 50 π 157.08
- 25 π 78.54
Answer
D. 25 π 78.54
Solution
Complete the squares: (x+4)2+(y-3)2=25, so r=5 and A=π r2=25π 78.54.
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