7.2x10=72
This should be the correct answer
<h3>
Answer: sqrt(20)</h3>
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Explanation:
Count out the spaces, or use subtraction, to find the horizontal side BC is 2 units long. Similarly, you'll find the vertical side AC is 4 units long.
Use the pythagorean theorem to find the length of segment AB.
a^2 + b^2 = c^2
2^2 + 4^2 = c^2
4 + 16 = c^2
20 = c^2
c^2 = 20
c = sqrt(20)
We stop here since it matches with choice B.
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Optionally, we can simplify like so
sqrt(20) = sqrt(4*5)
sqrt(20) = sqrt(4)*sqrt(5)
sqrt(20) = 2*sqrt(5)
By dividing each general term by 3.
Example:
(3/3=1)