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Todd draws a diagram using four identical right triangles to form a square as shown. Which best describes how to use the areas of the shaded triangles to begin a proof of the Pythagorean theorem? (picture included)

What is the length of bc ? enter your answer in the box.bc =

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.

Is triangle jkl congruent to triangle rst? if so, what is the scale factor?