Question

3. AB is the diameter of a circle with centre C(2,5). If A(6,2), find the co-ordinates of B.​

Answer 1

Answer:

(i) The length of radius AC=

(−2−3)

2

+(5+7)

2

=

(−5)

2

+(12)

2

=

25+144

=

169

=13.

(ii) Let the point of B be (x,y).

Given C is the mid-point of AB. Therefore

−2=

2

3+x

; 5=

2

−7+y

⇒3+x=−4 ⇒10=−7+y

⇒x=−4−3=−7 ; y=17

Hence, the co-ordinate of B≡(−7,17).