2.P. S. 89 is having an ice cream social for the graduating 8th grader. a
Ms. Gallo has to order the ice cream. She decided to order 21 cartons of vanilla ice cream and 28 cartons of
chocolate ice cream. Let V to represent cost of the vanilla ice cream and C to represent the chocolate ice cream.
Write an algebraic expression that represents the total cost of buying the ice cream
b.
Write an equivalent expression for your answer in part (a).
c. Explain why the expressions are equivalent. NO LINKS

Given: ab ≅ cd and ad ≅ bc prove: abcd is a parallelogram. statements reasons 1. ab ≅ cd; ad ≅ bc 1. given 2. ac ≅ ac 2. reflexive property 3. △adc ≅ △cba 3. ? 4. ∠dac ≅ ∠bca; ∠acd ≅ ∠cab 4. cpctc 5. ∠dac and ∠bca are alt. int. ∠s; ∠acd and ∠cab are alt. int. ∠s 5. definition of alternate interior angles 6. ab ∥ cd; ad ∥ bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3? triangle angle sum theorem sas congruency theorem sss congruency theorem cpctc