1. Dana has driven her car 95,598 miles. She estimates she can drive the car another 5000 miles before the mileage reaches 100,000 miles. Use the rules for estimating differences to explain if Dana is correct. Write About It 2. The estimated difference between 432,987 and a number, x, is 100,000. What is the greatest possible value of x? Explain how you got your answer.

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem