Suppose $\frac{\pi}{2}<\theta<\pi$ And $\tan (\theta)=-\frac{6}{7}$ Evaluate:
A) Sin

Suppose $\frac{\pi}{2}<\theta<\pi$ and $\tan (\theta)=-\frac{6}{7}$ . Evaluate:
A) sin( $\theta$ )
B) cos( $\theta$ )
Give the exact answers.