Let rst and vwx be the two similar triangles.

Since the ratio of sides rt and vx is b, the ratio of other corresponding sides would also be the same, because the triangles are similar. This means that the scale factor of triangles rst and vwx is b.

The ratio of the areas of the two triangles would therefore be b² . This means that the area of triangle rst divided by the area of triangle vwx would be b².

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