Estimate the probability of selecting zebra.

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

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

How do you do the foil method with polynomials?