You forgot to expand and simplify it... you only did step one, carry on your doing great 4 marks doesn’t come easy :)
A because the y intercept is the staring point
Answer:

Explanation:
A circle whose center is
and radius
, has equation:

The center of circle is given as origin
, therefore:

This circle passes
, then the radius of circle is the distance
between origin
and 

=> 
Substitute
,
, and
back into original equation:

or

Hope this helps!
:)
Answer:
The sum of 81 is 9*9=81
Step-by-step explanation: