Final answer:
To convert the given general ellipse equation to standard form, we group x and y terms, factor out their coefficients, complete the square for both, and divide by the constant to achieve the equation (x + 3)^2/4 + (y + 5)^2/6 = 1.
Step-by-step explanation:
To rewrite the equation of an ellipse from general form to standard form, we need to complete the square for both the x and y variables. The given equation is 3x^2 + 2y^2 + 18x + 20y + 65 = 0. To make this easier, we have to group the x terms and y terms.
First, let's rearrange the terms:
3x^2 + 18x + 2y^2 + 20y = -65
Next, we factor the coefficients of x^2 and y^2 out of the first and third terms respectively:
3(x^2 + 6x) + 2(y^2 + 10y) = -65
We will now complete the square for each group by adding and subtracting the respective squared half of the coefficient of x and y to each group. Remember to multiply the added terms outside the parentheses by the factor we factored out:
3[(x^2 + 6x + 9) - 9] + 2[(y^2 + 10y + 25) - 25] = -65
3[(x + 3)^2] - 27 + 2[(y + 5)^2] - 50 = -65
3(x + 3)^2 + 2(y + 5)^2 = -65 + 27 + 50
3(x + 3)^2 + 2(y + 5)^2 = 12
Finally, we need to divide everything by 12 to get the standard form of the ellipse equation:
(x + 3)^2/4 + (y + 5)^2/6 = 1