Question 597439
It it is a right triangle, then by Theorem of Pythagoras, {{{a^2 + b^2 = c^2}}}.


In this case, this is true ONLY in D. 5 cm, 12 cm, 13 cm.


{{{5^2 + 12^2 =13^2}}}
{{{25 + 144 = 169}}}


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Near the top of my homepage, look for the link "Basic, Intermediate, and College Algebra: One Step at a Time", and choose Basic Algebra (Chapter 2). Look for Section 2.10 THEOREM OF PYTHAGORAS.

 
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Dr. Robert J. Rapalje, Retired Professor of Mathematics
Seminole State College of Florida