Please help me in precal

Find the given elements if matrix d:

Which equations represents circles that have a diameter of 12 units and a center that lies on the y-axis? check all that apply

Question: a) does the given set of points represent a linear function? how do you know? b) assume that the point (-2,4) lies on the graph of a line. what y-values could complete this set of ordered pairs that lie on the same line: (- (hint: there are several correct answ