Answer:
8 and 12
Step-by-step explanation:
The perimeter of the given rectangle is ...
P = 2(L +W)
P = 2(14 +21) = 2(35) = 70
The scale factor to the similar triangle is ...
similar perimeter/original perimeter = 40/70 = 4/7
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The dimensions of the similar triangle are the original triangle dimensions multiplied by this scale factor:
(14)(4/7) = 8
(21)(4/7) = 12
The sides of the similar triangle are 8 and 12.
