Jamie needs to determine the distance across a river. She selects a rock, R, on the opposite river bank. She finds a tree, T, on her side of the river such that
RT
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¯
¯
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is perpendicular to the river.
Next, Jamie walks 50 yards down the river from the tree, T, to a spot, C. Using a compass that she made from two sticks, she measures
∠TCR
. She then walks from C in a direction that makes the same angle as
∠TCR
with the river bank on her side of the river. She keeps walking in that direction until she sees the tree and the rock in a straight line from her position. She marks this point B and then paces from B to T to measure the distance from point B to the tree. If BT turns out to be 75 yards, what is RT, the distance across the river