A-Level Maths: C2-05 [Circles: Using Completing the Square to find the Centre & Radius]

[dylantomkins]

Hi Jack, what do you think about factorising the coefficient of x/y squared out first, is there much difference?

[InternationalBites]

cant we keep the 4th and 5th in the form of a(x+b)-b^2 form

[yeshwanth]

Sir, they can also be done by
X²+Y²+cX+dY+e=0, then
Centre(-c/2, -d/2)
Radius=underroot c²+d²-e

[emilydunn]

For the third one, when you added 1/2 to each side, where did the half on the left hand side of the equation go?

[davidoloughlin]

What does the transformation actually mean if a coefficient greater than one is put before x^2 or y^2

[frankdandrea]

As you took the 100 out of the bracket in the last question do you not have to multiply it by 100 again?

[madiha]

Sir, for Q4, half of -14y is -8 ?? (i don't know I'm not sure) did you write the bracket _.__._.(y-4/5)^2??? also thank you so much sir!

[annechy_]

for the last one it doesnt = 24 but 23.1189 where did the 24 come from?