Answer:
Step-by-step explanation:
The triangles are all similar, so corresponding sides are proportional.
__
x
long side/short side = x/6 = 12/x
x² = 72 . . . . . . . multiply by 6x
x = 6√2 . . . . . . take the square root
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y
hypotenuse/long side = y/12 = (12+6)/y
y² = 216 . . . . . multiply by 12y
y = 6√6 . . . . . take the square root
