Apply the distributive property to factors out the greatest common factor of 15+21

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

Two numbers have a sum of -19. one number is x. what expression represents the other number?

Write the function for the graph. (1.8) (0,4)