Thursday

March 26, 2015

March 26, 2015

Posted by **Abbey(Please help)** on Monday, May 3, 2010 at 1:49pm.

9x^2 + 4y^2 - 36x + 8y + 31 = 0

My answer was:

center=(2,1)

v=(-2,10)(-2,-10)

f=(-2,11)(-2,-11)

e=11/3

Where did I make a mistake?

- Math -
**Reiny**, Monday, May 3, 2010 at 3:56pm9x^2 + 4y^2 - 36x + 8y + 31 = 0

9(x^2 - 4x + ...) + 4(y^2 + 2y + ...) = -31

9(x^2 - 4x + 4) + 4(y^2 + 2y + 1) = -31+36+4

9(x-2)^2 + 4(y+1)^2 = 9

(x-2)^2 + (y+1)^2 /(9/4) = 1

my centre is (2,-1)

a^2 = 1

b^2 = 9/4) etc

have you found your error?

- Math -
**Anonymous**, Tuesday, August 28, 2012 at 7:07pm9^2-[(4.2x3.4)-9.28

**Answer this Question**

**Related Questions**

Math - Find the center, vertices, foci, and eccentricity of the ellipse. 9x^2 + ...

Pre-calculus - For the ellipse with equation 5x^2+64y^2+30x+128y-211=0, find the...

Pre-Cal - Find the standard form of the equation of the ellipse. (Remember ...

alg2 - identify the conic section. if its a parabols give the vertex if its a ...

alg - identify the conic section. if its a parabols give the vertex if its a ...

Math - Ellipses [(x+3)^2 / 12] + [(y-2)^2 / 16] I Have to find the following: ...

Algebra II-Please check my calculation - Find center, vertices, co-vertices and ...

math - Find the vertices, foci and eccentricity of the ellipse.Thank you 9x^2 + ...

math - Find the vertices, foci, and eccentricity of the ellipse. Thank you. x^2/...

Math/Conics - Find the center, vertices, and foci of the ellipse with the ...