Calculating the length of one of the shorter sides

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Rearrange to calculate the length of one of the shorter sides.

\(a^2 + b^2 = c^2\) calculates the length of the longest side.

To calculate the length of one of the shorter sides, rearrange the formula to make \(a^2\) or \(b^2\) the subject.

\(a^2 = c^2 - b^2\) or \(b^2 = c^2 - a^2\)

Then take the square root to calculate the length \(a\) or \(b\).

Calculate the length AB.

\(a^2 + b^2 = c^2\)

\(8^2 + b^2 = 10^2\)

Rearrange the formula to make \(b^2\) the subject:

\(b^2 = 10^2 - 8^2\)

\(b^2 = 36\)

\(b = \sqrt{36}\)

\(b = 6~\text{cm}\)

The length AB is 6 cm.

Question

Calculate the length AO. Give the answer to one decimal place.