Which number is IRRATIONAL?
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Answer:
C)√ 72
Step-by-step explanation:
We will Simplify the radical by breaking the radicand up into a product of known factors.
When we do this, we figure out that...
A.√ 49 = 7
B.√ 64 = 8
D.√ 121 = 11
BUT C) is different.
√ 72 can not be divided into any whole number an exact amount of times.
So instead, this can be solved by writing it as shown:
Exact Form:
6 √ 2
Decimal Form:
8.48528137
Thanks for letting me help!!