Write the expression in terms of sine and cosine, and simplify so that no quotients appear in the final expression.
-Find $\cos ( \mathrm { s } - \mathrm { t } )$ given that $\cos \mathrm { s } = - \frac { 12 } { 13 }$, with $\mathrm { s }$ in quadrant II, and $\sin t = \frac { 8 } { 17 }$, with $\mathrm { t }$ in quadrant II.
A) $- \frac { 220 } { 221 }$
B) $\frac { 140 } { 221 }$
C) $\frac { 220 } { 221 }$
D) $- \frac { 140 } { 221 }$

Question

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The Answer of Write the expression in terms of sine and cosine, and simplify so that no quotients appear in the final expression.
-Find $\cos ( \mathrm { s } - \mathrm { t } )$ given that $\cos \mathrm { s } = - \frac { 12 } { 13 }$, with $\mathrm { s }$ in quadrant II, and $\sin t = \frac { 8 } { 17 }$, with $\mathrm { t }$ in quadrant II.
A) $- \frac { 220 } { 221 }$
B) $\frac { 140 } { 221 }$
C) $\frac { 220 } { 221 }$
D) $- \frac { 140 } { 221 }$

Write the Expression in Terms of Sine and Cosine, and Simplify