What is the locus of point that is equidistant from points P(1,3) and Q(3,5)?

In the diagram, KS is a tangent to the circle centre O at R and ∠ROQ = 80º. Find ∠QRS.

Find the equation of a line parallel to y = -4x + 2 passing through (2,3)

Find the distance between the points (\(\frac{1}{2}\), \(\frac{1}{2}\)) and (-\(\frac{1}{2}\), -\(\frac{1}{2}\)).

Find the gradient of the line passing through the points P(1, 1) and Q(2, 5).