Question 1004817
Knowing foci and that center is at the origin gives you a number, c; the co-vertices give you the number, b. The relationship among certain constants for an ellipse is {{{c^2=a^2-b^2}}}, which all come from the derivation of an ellipse's equation.


{{{system(c=1,b=4,highlight_green(a^2=c^2+b^2=1+16=17))}}}


Fill-in the standard form equation for the ellipse centered at origin as described:
{{{x^2/a^2+y^2/b^2=1}}}



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Learn to understand and use the standard form equations for an ellipse, and the meanings of the variables which occur in the derivation of the equation.  LOOK!  {{{highlight_green(a^2=17)}}}.