Question

The center of a circle is (4, 6), and an endpoint of a diameter is (2, 5). What is the other endpoint of the diameter

Answer 1

try to visualize the points as a straight line through a circle.. the midpoint has the coordinates [4,6] (lets call them x1,y1) and one end has [2,5] (or x2,y2).. You know that the line goes straight through the circle so both ends should be at an equal distance from the midpoint at the exact opposite side. So the equation for x3 = x1+(x1-x2). The same goes for y.. draw it out if you don't get it, it's easy ones you can see it.