SOLUTION: find the area of an ellipse 13x^2+121y^2=1

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Question 836970: find the area of an ellipse 13x^2+121y^2=1
Found 2 solutions by lwsshak3, Edwin McCravy:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
find the area of an ellipse
13x^2+121y^2=1
x%5E2%2F%281%2F13%29%2By%5E2%2F%281%2F121%29=1
Area of ellipse=π*a*b
a=1/13
b=1/121
π*a*b=π*1/13*1/121=π/1573 sq units

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
The other tutor has the formula for the area of an ellipse wrong.

13x%5E2%22%22%2B%22%22121y%5E2%22%22=%22%221

Put 1 under the term on the left

13x%5E2%2F1%22%22%2B%22%22121y%5E2%2F1%22%22=%22%221

In the first term divide top and bottom by 13
In the second term divide top and bottom by 121

%2813x%5E2%2F13%29%2F%281%2F13%29%22%22%2B%22%22%28121y%5E2%2F121%29%2F%281%2F121%29%22%22=%22%221

Cancel:

%28cross%2813%29x%5E2%2Fcross%2813%29%29%2F%281%2F13%29%22%22%2B%22%22%28cross%28121%29y%5E2%2Fcross%28121%29%29%2F%281%2F121%29%22%22=%22%221

x%5E2%2F%281%2F13%29%22%22%2B%22%22y%5E2%2F%281%2F121%29%22%22=%22%221

Compare to 

x%5E2%2Fa%5E2%22%22%2B%22%22y%5E2%2Fb%5E2%22%22=%22%221

a%5E2=1%2F13,   b%5E2=1%2F121

a=sqrt%281%2F13%29=sqrt%2813%29%2F13,   b=sqrt%281%2F121%29=1%2F11

Area=pi%2Aa%2Ab=pi%28sqrt%2813%29%2F13%29%281%2F11%29=pi%2Asqrt%2813%29%2F143

approximately 0.0792110028

A pretty small ellipse:



Edwin