Question 328447
({{{-a}}},{{{0}}}) and ({{{a}}},{{{0}}})
({{{-5}}},{{{0}}}) and ({{{5}}},{{{0}}})
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{{{drawing(300,300,-6,6,-6,6,circle(-5,0,.3),circle(5,0,.3),grid(1),graph(300,300,-6,6,-6,6,sqrt(9(1-x^2/25))),graph(300,300,-6,6,-6,6,-sqrt(9(1-x^2/25))))}}}