15. Which of the following systems represent the graph shown? A) 2x + 3y < 6
-x + y > -4

B) 2x + 3y _> 6
-x + y _> -4

C) x + y >_ 4
2x - 3y <_ 6

D) x + y > 4
2x - 3y < 6

What is the next step in the given proof? choose the most logical approach. a. statement: m 1 + m 2 + 2(m 3) = 180° reason: angle addition b. statement: m 1 + m 3 = m 2 + m 3 reason: transitive property of equality c. statement: m 1 = m 2 reason: subtraction property of equality d. statement: m 1 + m 2 = m 2 + m 3 reason: substitution property of equality e. statement: 2(m 1) = m 2 + m 3 reason: substitution property of equality