Any help? Explanation would help massively too! Work out the length of AB

Exact length = 2*sqrt(137)   cm

Approximate length = 23.409  cm

Work Shown:

Use the Pythagorean theorem

a^2 + b^2 = c^2

8^2 + 22^2 = c^2

64 + 484 = c^2

548 = c^2

c^2 = 548

c = sqrt(548)

c = sqrt(4*137)

c = sqrt(4)*sqrt(137) use the rule sqrt(x*y) = sqrt(x)*sqrt(y)

c = 2*sqrt(137)   this is the exact length

c = 23.4093998214392 ... use your calculator to find the approximate length

c = 23.409

I rounded to three decimal places, but feel free to round however you want. Or be sure to follow any rounding instructions your teacher provides.