standard_description: Draw polygons in the coordinate plane given coordinates for the vertices; use coordinates to find the length of a side joining points with the same first coordinate or the same second coordinate. Apply these techniques in the context of solving real-world and mathematical problems.
problem_activity: Task
The table below shows all the products of pairs of numbers between 1 and 9.
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Which numbers appear only once in the table of products?   Where are these numbers located in the table?  Why?
Which numbers appear the most frequently in the table?  Why?
Which numbers between 10 and 20 do  not  appear in the table?  What do these numbers have in common?


aligns: no