AQA C1 2013 June — Question 3

Exam BoardAQA
ModuleC1 (Core Mathematics 1)
Year2013
SessionJune
TopicCircles

3 A circle \(C\) has equation $$x ^ { 2 } + y ^ { 2 } - 10 x + 14 y + 25 = 0$$
  1. Write the equation of \(C\) in the form $$( x - a ) ^ { 2 } + ( y - b ) ^ { 2 } = k$$ where \(a , b\) and \(k\) are integers.
  2. Hence, for the circle \(C\), write down:
    1. the coordinates of its centre;
    2. its radius.
    1. Sketch the circle \(C\).
    2. Write down the coordinates of the point on \(C\) that is furthest away from the \(x\)-axis.
  3. Given that \(k\) has the same value as in part (a), describe geometrically the transformation which maps the circle with equation \(( x + 1 ) ^ { 2 } + y ^ { 2 } = k\) onto the circle \(C\).