Find Sin(P + Q) from 2 equations

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Homework Statement


In triangle PQR, 3SinP + 4CosQ = 6 and 4SinQ + 3CosP = 1. a) Find sin(P + Q). b) Determine the measure of angle R, in radians. The answer given for part a) is 1/2 and part b) pi/6

Homework Equations


Sin (A+B) = SinACosB + CosASinB

The Attempt at a Solution


Handwritten-style algebra working: 3SinP + 4CosQ = 6 and 4SinQ + 3CosP = 1, rearranged to SinP = 2 - 4/3CosQ and CosP = 1/3 - 4/3SinQ, then substituted into Sin(P + Q) = SinPCosQ + CosPSinQ and simplified step by step.


Thats what I've tried and I simply don't understand how to solve it...
 
Try squaring your expressions for sin P and cos P and adding them together and simplify the resulting equation using the identity sin2 x + cos2 x = 1. I think that'll let you eventually solve for Q. Once you have Q, you can solve for P.