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M2

Here we have placed the two triangles next to each other.

They are not as different as they may have appeared at first sight:
two pairs of corresponding sides are the same;
and the angles between those sides, though not the same, are supplementary.

This means that the triangles would nicely fit together, with their bases forming a straight line and with the triangles having a common height.

A neater way of fitting the triangles together is shown NEXT.