The equation of a circle is x2 + y2 + 8x – 2y =1. (i) State the coordinbites of its centre and find the exact length of its radius.
(ii) Prove that the point P(-7,4) lies on its circumference.
(iii) Given that PQ is a diameter, determine the coordinates of Q.
(iv) Find the equation of the tangent at the point Q.

a. she will receive a refund of $278.

step-by-step explanation:

step-by-step explanation: given equation a = h(b 1+b 2)

also we are given values of a, h and b 1 as :

a = 16, h = 4, and b 1 = 3.

in order to solve it for b 2, we need to plug the given values of   a, h and b 1 .

therefore, plugging values of   a, h and b 1   in given equation, we get

16 = 4( 3 + b 2)

first dividing both sides by 4, we get

4 = 3 + b 2

subtracting 3 from both sides, we get

4 -3 = 3 -3 + b 2

1 = b 2.