Assume that the banner needs to be 18 feet long how wide can it be to have enough ribbon to go around ? rewrite the inequality using an 18foot length instead of 15 feet ?

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b