Question 303171
Foci
{{{a^2=b^2+c^2}}}
{{{25=16+c^2}}}
{{{c^2=9}}}
{{{c= 0 +- 3}}}
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{{{ drawing( 300, 300, -8, 8, -8, 8, grid(1),circle(-3,0,.3),circle(3,0,.3),graph( 300, 300, -8, 8, -8, 8, sqrt(16(1-x^2/25)),-sqrt(16(1-x^2/25))))}}}