The Oakland School's harvest festival is coming up, and Ms. Garza is in charge of ordering the caramel apples again. She knows she ordered 9 cases of caramel apples last year but can't remember how many apples come in a case. She checks last year's records and finds that the school sold 685 caramel apples and had 35 left over. Which equation can Ms. Garza use to find how many caramel apples, c, come in each case?

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?