167k views
5 votes
Use the following equation change it by completing the square. Then find the vertex, Axis of Symmetry, Focus , Directrix, which way it opens and the Latus Rectum. x+3y^2+32y+20

User Doogle
by
8.6k points

1 Answer

5 votes

Final answer:

To complete the square of the given quadratic equation, we rearrange the terms and add/subtract the square of half the coefficient of y. The vertex is (-20, -16), the axis of symmetry is x = -20, the focus is (20, 240), the directrix is y = -272, the equation opens upwards, and the latus rectum has a length of 1024.

Step-by-step explanation:

To complete the square for the given quadratic equation, x + 3y^2 + 32y + 20, we rearrange the terms to group the x and y terms together. The equation becomes (y^2 + 32y) + (x + 20). To complete the square on the y terms, we need to add and subtract the square of half the coefficient of y, which is (32/2)^2 = 256. We also need to add and subtract the same value inside the parentheses to balance the equation. So, the equation becomes (y^2 + 32y + 256) - 256 + (x + 20).

The vertex form of the equation is now (y + 16)^2 - 256 + (x + 20). The vertex of a quadratic equation in the form (y + k)^2 + h is given by (-h, -k). Hence, the vertex of the given equation is (-20, -16).

The axis of symmetry of a quadratic equation is a vertical line passing through the vertex. Thus, the equation's axis of symmetry is x = -20.

The focus and directrix of a quadratic equation in the form (y + k)^2 + h are given by (h, k + p) and y = k - p, respectively, where p is the distance from the vertex to the focus or directrix. In this equation, p = 256, so the focus is at (20, -16 + 256) = (20, 240) and the directrix is y = -16 - 256 = -272.

The given equation opens upwards because the coefficient of y^2 is positive.

The latus rectum is a line segment passing through the focus and perpendicular to the axis of symmetry. Its length is equal to 4p, where p is the distance from the vertex to the focus. In this case, the latus rectum has a length of 4 * 256 = 1024.

User Mszaro
by
7.0k points