What is the unknown side length?

Answer:
unknown side length = 6.928
Step-by-step explanation:
8^2 - 4^2 = 48 = 6.928^2
Answer:
6.928 (round up to your choosing)
Step-by-step explanation:
(4)²+x²=(8)²
16+x²=64
x²=48
x=√48
x≈6.9
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