Problem What is the radius of the circle $x^2 + y^2 - 6x = 0$?
Answer Key
Solution
$(x^2 - 6x) + y^2 = 0$
$(x^2 - 6x + \color{#FFFF66}{9}) + y^2 = \color{#FFFF66}{9}$
$(x - 3)^2 + y^2 = 3^2$
center = (3, 0) radius = 3 ← answer
Follow @iMATHalino
MATHalino