X² + 5Y² + 5X + 25Y = 100
Completamos cuadrados para X
X² + 5X + 6.
25 - 6.
25 = (X² + 5X + 6.
25) - 6.
25 = (X + 2.
5)² - 6.
25
Completamos cuadrados para Y
5Y² + 25Y = 5[Y² + 5Y + 6.
25 - 6.
25] = 5(Y + 2.
5)² - 31.
25
(X + 2.
5)² + 5(Y + 2.
5)² - 31.
25 - 6.
25 = 100
(X + 2.
5)² + 5(Y + 2.
5)² - 37.
5 = 100
(X + 2.
5)² + 5(Y + 2.
5)² = 137.
5 : Divido toda la expresion entre 137.
5
[(X + 2.
5)² / 137.
5] + [5(Y + 2.
5)² / 137.
5] = 1
[(X + 2.
5)² / 137.
5] + [(Y + 2.
5)² / 27.
5] = 1
<img src="https://tex.z-dn.net/?f=%5Cfrac%7B%5Cleft%28x-h%5Cright%29%5E2%7D%7Ba%5E2%7D%2B%5Cfrac%7B%5Cleft%28y-k%5Cright%29%5E2%7D%7Bb%5E2%7D%3D1" /> - h = 2.
5 ; h = - 2.
5 ; - k = 2.
5 ; k = 2.
5
Centro ( - 2.
5 , - 2.
5)
a² = 137.
5 , b² = 27.
5,
<img src="https://tex.z-dn.net/?f=a%3D%20%5Csqrt%7B137.5%7D%3D11.726%20" /> ; <img src="https://tex.z-dn.net/?f=b%3D%20%5Csqrt%7B27.5%7D%3D5.244" />
Vertices : [( - 11.
762 - 2.
5) , - 2.
5] y [( + 11.
762 - 2.
5) , - 2.
5]
Vertices : [ - 14.
262 , - 2.
5] y [9.
262 , - 2.
5]
Focos tenemos que hallar c
c² = a² - b² = 137.
5 - 27.
5 = 110
<img src="https://tex.z-dn.net/?f=c%3D%20%5Csqrt%7B110%7D%3D10.488%20" />
Focos : [( - 10.
488 - 2.
5) , - 2.
5] y [( + 10.
488 - 2.
5) , - 2.
5] [ - 12.
988 , - 2.
5] y [7.
988 , - 2.
5]
Centro en ( - 2.
5 , - 2.
5)
Semieje mayor = a = 11.
726
Semieje menor = b = 5.
244
Vertices : [ - 14.
262 , - 2.
5] y [9.
262 , - 2.
5]
Focos : [ - 12.
988 , - 2.
5] y [7.
988 , - 2.
5]
Te anexo una grafica de la elipse.