Answer:
(0,12) y axis
(3,-7) quadrant 4
(-15,21) quadrant 2
(18,0) x axis
(4.5, 10.6) quadrant 1
(-34,-419) quadrant 3
Explanation:
if (number,0) it is on the x axis
if (0, number) it is on the y axis
if (+ ,+) quadrant 1
(+, -) quadrant 4
(-,-) quadrant 3
(-,+) quadrant 2