Last visit was: 26 Dec 2024, 19:43 It is currently 26 Dec 2024, 19:43
Decision Tracker
My Rewards
New comers' posts
New posts
Unanswered

Close

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

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GRE score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel
PREVIOUS TOPIC
NEXT TOPIC

x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation

Tags :
Find Similar Topics  About  Add a Tag

Show Tags
Hide Tags

User avatar
D
KarunMendiratta
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Own Kudos [?]: 3271 [2]
Given Kudos: 172
Location: India
WE:Education (Education)
Send PM
x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation [#permalink] New post   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
ShowHide Answer
Official Answer
B
User avatar
D
KarunMendiratta
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Own Kudos [?]: 3271 [2]
Given Kudos: 172
Location: India
WE:Education (Education)
Send PM
x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation [#permalink] New post   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
User avatar
bumpbot
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5091
Own Kudos [?]: 76 [0]
Given Kudos: 0
Send PM
Re: x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation [#permalink] New post   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.
Prep Club for GRE Bot
gmatclubot
Re: x^2 + y^2 - 6x + 8y = 56, What is the area of a circle whose equation [#permalink]
19 Sep 2022, 22:31
Moderators:
adewale223
GRE Instructor
88 posts
bronaugust
GRE Forum Moderator
37 posts
BrushMyQuant
Moderator
1115 posts
VibhuAnurag
GRE Instructor
234 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Main navigation

Partners

GRE Resources

www.ets.org/gre | About | Terms and Conditions and Privacy Policy | Prep Club for GRE Rules | Contact