You buy the same number of brushes, rollers and paint cans. write an expression in simples form that represents the total amount of money you spend for painting supplies. paint $21.79
brush $3.99 and paint roller $6.89

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