find the length of side a.
Hurry please no trolling.
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Answer:
A. 5
Step-by-step explanation:
use pythagorean theorem: a^2 + b^2 = c^2
but since we are finding the value of A; we'll use a= (square root) c^2 - b^2
A= 13^2- 12^2
A= 169 - 144
A= 25
A= 5 ( because we square root 25)