## sima_zhao 3 years ago can anyone help me figure out a new equation for an ellipse whose length and width are doubled and the original equation is x^2/50+y^2/20=1

1. KDroid

Find out a & b. Multiply them with 2. & put'em in the general equation of the ellipse. :)

2. Cynosure-EPR

KDroid is correct, but I'll give you a bit more: You want to take the square root of the numbers in the denominator of the 'x' and 'y' slots to get 'a' and 'b' (so 50 and 20 respectively; square root to get a=7.07 and b =4.46). That will give you the points on the x-axis and y-axis of which your ellipse crosses. Double this number and re-square it to get it back in the form you started in. So, $\sqrt{50} = 7.07$ $7.0*2 = 14.1421$ $14.1421^{2} = 200$ 200 is the new value under your 'x'. Do the same for the 'y' and you should get 80.