Final answer:
The points (1½,4) and (-2,-2½) lie in the first and third quadrants, respectively, as the first has both positive coordinates and the third has both negative coordinates.
Step-by-step explanation:
The coordinate plane that contains the points (1½,4) and (-2,-2½) can be determined by looking at the signs of the coordinates. The point (1½,4) lies in the first quadrant because both coordinates are positive. Moving vertically upward in the coordinate system represents an increase in the y-value, while moving horizontally to the right side of the coordinate system represents an increase in the x-value. The point (-2,-2½) lies in the third quadrant because both x and y coordinates are negative. Moving vertically downward in the coordinate system or horizontally to the left side would indicate negative x or y values.
Since the question asks for a singular plane that contains both points, no such quadrant exists because these points lie in 2 different quadrants.