Find the length of the third side. If necessary, write in simplest radical form.
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Answer:
the length of the missing side is 2
Step-by-step explanation:
Use a^2 + b^2 = c^2
a = 4
b = ?
c = 2sqrt5
4^2 + b^2 = (2sqrt5)^2
16 + b^2 = 20
subtract 16 from both sides
b^2 = 4
take the sqrt of both sides
b = 2