GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Given Kudos: 172
Location: India
WE:Education (Education)
x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation
[#permalink]
19 Mar 2021, 23:06
19 Mar 2021, 23:06
2
Bookmarks
00:00
Question Stats:
50% (00:44) correct
50% (01:40) wrong based on 4 sessions
Hide Show timer Statistics
\(x^2 + y^2 - 6x + 8y = 56\)
What is the area of a circle whose equation is given above?
A. \(25π\)
B. \(81π\)
C. \(162π\)
D. \(6,561π\)
E. Cannot be determined
What is the area of a circle whose equation is given above?
A. \(25π\)
B. \(81π\)
C. \(162π\)
D. \(6,561π\)
E. Cannot be determined
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Given Kudos: 172
Location: India
WE:Education (Education)
x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation
[#permalink]
20 Mar 2021, 22:39
20 Mar 2021, 22:39
1
1
Bookmarks
Explanation:
Equation of a circle is \((x-h)^2 + (y-k)^2 = r^2\)
Where, \((h, k)\) are the coordinates of the centre and \(r\) is the radius
\(x^2 + y^2 - 6x + 8y = 56\)
\(x^2 - 6x + y^2 + 8y = 56\)
\(x^2 + 9 - 6x + y^2 + 16+ 8y = 56 + 9 + 16\)
\((x-3)^2 + (y+4)^2 = 81\)
Therefore, Centre \(= (3, -4)\) and \(r = 9\)
Area = \(81π\)
Hence, option B
Equation of a circle is \((x-h)^2 + (y-k)^2 = r^2\)
Where, \((h, k)\) are the coordinates of the centre and \(r\) is the radius
\(x^2 + y^2 - 6x + 8y = 56\)
\(x^2 - 6x + y^2 + 8y = 56\)
\(x^2 + 9 - 6x + y^2 + 16+ 8y = 56 + 9 + 16\)
\((x-3)^2 + (y+4)^2 = 81\)
Therefore, Centre \(= (3, -4)\) and \(r = 9\)
Area = \(81π\)
Hence, option B
Re: x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation
[#permalink]
19 Sep 2022, 22:31
19 Sep 2022, 22:31
Hello from the GRE Prep Club BumpBot!
Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
