An eighth-grade student claims she can prove that subtraction of integers is commutative. she points out that if a and b are integers, then

a - b = a + (-b)

Data was collected on myrtle beach for 11 consecutive days. each day the temperature and number of visitors was noted. the scatter plot below represents this data. how many people visited the beach when the temperature was 84 degrees?

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog

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?