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Two lines parallel to a third line are parallel to each other. always sometimes or never

Ivan began dividing g2  – 6 by g + 1, noting that . he started by placing g in the quotient, as shown below.what is g2  – 6 divided by g + 1? g –  1 –  g + 1  – g  –  7 + g  –  5  + 

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