In the diagram, what is the area of rectangle PQRS?
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Solution
The width of rectangle PQRS is the horizontal distance between points P and Q (or points S and R), since these points have equal y-coordinates. This distance is equal to the difference between their x-coordinates or 4−(−4)=8. Similarly, the height of rectangle PQRS is equal the vertical distance between points S and P (or points R and Q), since these points have equal x-coordinates. This distance is equal to the difference between their y-coordinates or 2−(−2)=4. The area of rectangle PQRS is 8×4=32.
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