Below, I have posted a question and a solution I was provided. The problem is that I don't understand how the part bordered by AAA was arrived at. Specifically , & why it's simply multiplied against ? After multiplying that expression, I end up with , & not . Can anyone help clarify this for me, or is there a better approach?
Q. is the equation of a circle. 2 lines, L & M, intersect at (2, -2). The distance from the centre of the circle to each line is . Find the equation of L & M.
Attempt: Line equation for (2,-2):
From circle equation: centre c = (-1, 2)
Sub c into the line equation:
The distance from the point (-1, 2) to this line is
Ans. (From text book): &