Evaluate 2 4ac if b = 5, a = -2, and c = 0

In the image, point a marks the center of the circle. which two lengths must form a ratio of 1 : 2? (options are in the images since thought they were harmful phrases)

If given an equation of a line such as -1/2x+6 how would you create an equation of a line parallel and perpendicula to this line that goes through another point such as (4,10)

What is the point-slope equation of a line with slope -5 that contains the point (6,3)