We have to pause here and use an identity:
we use it to find cos(u) from sin(u):
Multiply through by 169
Subtract 25 from both sides:
We can determine which sign + or - to use because
we know that both are in Quadrant II, and the
cosine is negative in quadrant II. So
we can now substitute that in
But we still need sin(v). So we go back to the identity:
we use it to find sin(v) from cos(v):
Multiply through by 25
Subtract 9 from both sides:
As before we can determine which sign + or - to use because
we know that both are in Quadrant II, and the sine is
positive in quadrant II. So
we can now substitute that in
Answer:
Edwin