Match the base to the corresponding height.
Base (b)
Height (h)
b
b
h
b

See the diagram below

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Explanation:

The base is always perpendicular to the height, meaning the two form a 90 degree angle (aka right angle).

In column 1, refer to the figures as 1, 2 and 3 (working top to bottom).

In column 2, refer to the figures as A, B, C

Figure 1 matches with figure B

Figure 2 matches with figure C

Figure 3 matches with figure A.

These matches are of course the base with the proper height.

4x and 6y

im not sure though

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