Monoxdifly
MHB
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A circle L is going through the point O (0, 0) and P (6, 0). The center is in the line $$y=\frac{4}{3}x$$. The equation of the circle L is ...
A. $$x^2+y^2+6x-8y=0$$
B. $$x^2+y^2-6x-8y=0$$
C. $$x^2+y^2-8x-6y=0$$
D. $$x^2+y^2+8x+6y=0$$
E. $$x^2+y^2-4x-3y=0$$
Since the equation of a circle is $$x^2+y^2+Ax+By+C=0$$, I substituted both known points to the equation and got C = 0 as well as B = -6, so the answer is obviously B. But then my student asked "What if all options have -6 as their B? How would we know the answer?". I think it has something to do with that $$y=\frac{4}{3}x$$, but how? Please give me some hints.
A. $$x^2+y^2+6x-8y=0$$
B. $$x^2+y^2-6x-8y=0$$
C. $$x^2+y^2-8x-6y=0$$
D. $$x^2+y^2+8x+6y=0$$
E. $$x^2+y^2-4x-3y=0$$
Since the equation of a circle is $$x^2+y^2+Ax+By+C=0$$, I substituted both known points to the equation and got C = 0 as well as B = -6, so the answer is obviously B. But then my student asked "What if all options have -6 as their B? How would we know the answer?". I think it has something to do with that $$y=\frac{4}{3}x$$, but how? Please give me some hints.