Complete the square on the x and y terms on the LHS:
=> 5[x^2 + 2x] + 9[y^2 - 4y] = 4
=> 5[(x + 1)^2 - 1] + 9[(y - 2)^2 - 4] = 4
Expand:
=> 5(x + 1)^2 - 5 + 9(y-2)^2 - 36 = 4
=> 5(x+1)^2 + 9(y-2)^2 = 4 + 5 + 36 = 45
Divide through by 45 to get:
[(x + 1)^2]/9 + [(y - 2)^2]/5 = 1
=> [(x + 1)^2]/3^2 + [(y - 2)^2]/ (sqrt(5))^2 = 1
This is now of the form of an equation of an ellipse: (x-p)^2 / a^2 + (y-q)^2/b^2 = 1
Where the origin is point (p,q) and the foci are at +/-(ae,0) and e is the eccentricity and
e = sqrt(1 - b^2/a^2
and the ellipse meets the axis at (a,0), (-a,0), (0,b) and (0,-b) *** See extra note ***
Hence we have p = -1 and q = 2
Hence centre at point (-1, 2)
Also, a = 3 and b = sqrt(5). hence vertices at (3,0), (-3,0), (0,sqrt5) and (0, -sqrt5)
e = sqrt(1 - 5/9) = sqrt(4/9) = 2/3
Hence foci at +/- (3*2/3), 0) = +/- (2,0)
Extra note: Oh, just realised this gives the foci and vertices when centre is at origin. You will need to adjust each by the translation p,q. as necessary. Haven't got much time now.
My Vertex is in Libra interior the 6th homestead. Romantically, I often attraction to Geminis (opp my sunlight in Sag) if there is something romantic in those people, or Taurus (opp my Scorpio placements), and a few Leos (my Moon is in Leo). No Libra sunlight men so far whether some with planets in Libra (including Mars, Moon and Venus). a great form of Libra sunlight girlfriends yet I ditched them one via one, i'm reliable at exciting females yet some all people is taking it too far. I purely play the servant for a constrained volume of time.
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Verified answer
Rearrange to get:
5x^2 + 10x + 9y^2 - 36y = 4
Complete the square on the x and y terms on the LHS:
=> 5[x^2 + 2x] + 9[y^2 - 4y] = 4
=> 5[(x + 1)^2 - 1] + 9[(y - 2)^2 - 4] = 4
Expand:
=> 5(x + 1)^2 - 5 + 9(y-2)^2 - 36 = 4
=> 5(x+1)^2 + 9(y-2)^2 = 4 + 5 + 36 = 45
Divide through by 45 to get:
[(x + 1)^2]/9 + [(y - 2)^2]/5 = 1
=> [(x + 1)^2]/3^2 + [(y - 2)^2]/ (sqrt(5))^2 = 1
This is now of the form of an equation of an ellipse: (x-p)^2 / a^2 + (y-q)^2/b^2 = 1
Where the origin is point (p,q) and the foci are at +/-(ae,0) and e is the eccentricity and
e = sqrt(1 - b^2/a^2
and the ellipse meets the axis at (a,0), (-a,0), (0,b) and (0,-b) *** See extra note ***
Hence we have p = -1 and q = 2
Hence centre at point (-1, 2)
Also, a = 3 and b = sqrt(5). hence vertices at (3,0), (-3,0), (0,sqrt5) and (0, -sqrt5)
e = sqrt(1 - 5/9) = sqrt(4/9) = 2/3
Hence foci at +/- (3*2/3), 0) = +/- (2,0)
Extra note: Oh, just realised this gives the foci and vertices when centre is at origin. You will need to adjust each by the translation p,q. as necessary. Haven't got much time now.
My Vertex is in Libra interior the 6th homestead. Romantically, I often attraction to Geminis (opp my sunlight in Sag) if there is something romantic in those people, or Taurus (opp my Scorpio placements), and a few Leos (my Moon is in Leo). No Libra sunlight men so far whether some with planets in Libra (including Mars, Moon and Venus). a great form of Libra sunlight girlfriends yet I ditched them one via one, i'm reliable at exciting females yet some all people is taking it too far. I purely play the servant for a constrained volume of time.