triangle PQR

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triangle PQR

by canuckclint » Sun Oct 19, 2008 12:16 pm
Question please solve:
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by madeline » Sun Oct 19, 2008 8:07 pm
Rephrasing the question: PRS - PQR = ?

(1) QPR = 30
QPR + PQR = PRS
This is a basic property of triangles. If you didn't know it, think of it this way:
PRQ + QPR + PQR = 180
PRQ + PRS = 180
Therefore, QPR + PQR = PRS
Anyway, so 30 + PQR = PRS
PRS - PQR = 30
Statement 1 alone is sufficient.

(2) PQR + PRQ = 150
Since PQR + PRQ + QPR = 180
Therefore QPR = 30
Then this becomes statement 1, which is sufficient, so statement 2 alone is also sufficient.