Solve the system by substitution. 2x - y + z = -4
z = 5
-2x + 3y - z = -10

A. (–8, 7, 5)
B. (–8, –7, 5)
C. (8, –7, 5)
D. (–8, –7, –5)

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