Question

problem 9: from this given statement, select the definition, property, postulate, or theorem that justifies the prove statement. given: ∠1 + ∠4 = 180 and ∠2 + ∠3 = 180 prove: ∠1 + ∠4 = ∠2 + ∠3 a b c d e addition property

Explanation:

Step1: Analyze given equations

Given $\angle1+\angle4 = 180$ and $\angle2+\angle3=180$.

Step2: Apply substitution

Since both $\angle1 + \angle4$ and $\angle2+\angle3$ equal 180, by the transitive - property of equality (which is related to the addition property in the sense of equal - value substitution), we can say $\angle1+\angle4=\angle2+\angle3$. The addition property allows us to make such equal - value replacements when two expressions are equal to the same quantity.

Answer:

A. Addition Property