7. In a trapezoid, the diagonals of which intersect at a right angle, it is known that the midline is 6.5 and one of the diagonals is 12. Find the second diagonal

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# Answer 5

Solution: Let's parallel translate one of the diagonals so that it forms a right-angled triangle with the other. Then, in this triangle, one leg is 12, and the hypotenuse is 13, so the remaining leg is 5.

## Option $2-$ -