Help pls!! If AB= 8, what is BD in square ABCD??
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Answer:
option b
Step-by-step explanation:
sine all sides of a square are equal, AD = 8 too
therefore with pythagoras theorem,
AD^2 + AB^2 = BD^2
8^2 + 8^2 = BD^2
64 + 64 = BD^2
128 = BD^2
BD = root of 128 = 8 root 2 (b option)