Answer: 16 units
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Explanation:
Segment PJ is perpendicular to segment YZ
So triangle PJZ is a right triangle with the known leg ZJ = 12, unknown leg PJ = x, and known hypotenuse PZ = 20.
Let's say a = 12, b = x, c = 20.
Use the Pythagorean theorem to find x
a^2 + b^2 = c^2
12^2 + x^2 = 20^2
144 + x^2 = 400
x^2 = 400-144
x^2 = 256
x = sqrt(256)
x = 16
Therefore segment PJ is 16 units long.
Side note: the angle bisectors won't always form 90 degree angles with the opposite sides. These angle bisectors are also altitude lines because of the 90 degree angles that form.
