Find the length of the third side. If necessary, write in simplest radical form.
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Answer:
Third side = √7 units.
Step-by-step explanation:
Use Pythagoras Theorem:
4^2 = 3^2 + x^2
x^2 = 4^2 - 3^2 = (4-3)(4+3) = 7
x = √7.