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Show that the equation represents a circle by rewriting it in standard form, and find the center and radius of the circle.
x2 + y2 + 4y + 2 = 0
 one year ago
 one year ago
Show that the equation represents a circle by rewriting it in standard form, and find the center and radius of the circle. x2 + y2 + 4y + 2 = 0
 one year ago
 one year ago

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ShaksBest ResponseYou've already chosen the best response.0
Show that the equation represents a circle by rewriting it in standard form, and find the center and radius of the circle. x2 + y2 + 4y + 2 = 0
 one year ago

saifoo.khanBest ResponseYou've already chosen the best response.0
@Directrix are you good with circles?
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
@Shaks I'm hoping you understand the process of completing the square. We'll need that to get x2 + y2 + 4y + 2 = 0 into the standard form of the equation of a circle. That standard form is (x  h) ^2 + (y  k) ^2 = r^2 where (h,k) are the coordinates of the center of the circle and r is the radius of the circle. Check out the attachment.
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
No. Focus on the process, not the answer.
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
So, x^2 + y^2 + 4y + 2 = 0 can be written as x^2 + y^2 + 4y + __4_ = 0 + 4 (x + 0) ^2 + (y + 2) ^2 = 4 > Your Circle Now, look at the standard form for the circle equation, compare it to the equation, and pick out the coordinates of the center and the value of the radius. Post what you get, and I'll check. @Shaks
 one year ago

ShaksBest ResponseYou've already chosen the best response.0
x^2+(y+2)^2=3 is this the standerd form
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
Look at standard form for circle equation: That standard form is (x  h) ^2 + (y  k) ^2 = r^2 where (h,k) are the coordinates of the center of the circle and r is the radius of the circle. What positive number times itself = 4? That's your r.
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
@Shaks I messed up by dropping the 2. So, x^2 + y^2 + 4y + 2 = 0 can be written as x^2 + y^2 + 4y + __4_ = 2 + 4 = 6. r^2 = 6 and r is square root of 6.
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
6 = r^2. We want r which is square root of 3.
 one year ago

ShaksBest ResponseYou've already chosen the best response.0
did not get it it too doficult
 one year ago

DirectrixBest ResponseYou've already chosen the best response.0
You approximated square root of 3 to get 1.7. I stick with exact form but I don't know what your options are.
 one year ago

ShaksBest ResponseYou've already chosen the best response.0
Find all real solutions of the equation. (Enter your answers as a commaseparated list. If there is no real solution, enter NO REAL SOLUTION.) x + 42 = x
 one year ago
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