The Ellipse (x^2/9)+(y^2/16)=1 is _________
A) A vertical ellipse with foci at (0, +-sqroot7)
B) A horizontal ellipse with foci at (+-sqroot7, 0)
C) An ellipse with a minor axis of length 8
D) An ellipse with a major axis of length 6
thanks
The Ellipse (x^2/9)+(y^2/16)=1 is _________
A) A vertical ellipse with foci at (0, +-sqroot7)
B) A horizontal ellipse with foci at (+-sqroot7, 0)
C) An ellipse with a minor axis of length 8
D) An ellipse with a major axis of length 6
thanks
Hello, Andy!
We can "eyeball" the equation . . .
The ellipse . $\displaystyle \frac{x^2}{9}+ \frac{y^2}{16} \:=\:1$ .is:
(A) A vertical ellipse with foci at $\displaystyle (0,\,\pm\sqrt{7})$
(B) A horizontal ellipse with foci at $\displaystyle (\pm\sqrt{7},\,0)$
(C) An ellipse with a minor axis of length 8
(D) An ellipse with a major axis of length 6
We see that the major (longer) axis is in the y-direction, a "vertical" ellipse.
. . The length of the major axis is 8; the minor axis has length 6.
This eliminates answer-choices $\displaystyle (B),\,(C),\,(D)$