Question

A conjecture and a portion of the flowchart proof used to prove the conjecture are shown.

Which equation best represents the information that should be in the box labeled 1?

3x = 9

3x = 26

3x = 27

3x = 30

Answer 1

3x = 27

Explanation:

The addition property of equality, which is used to justify this step in the proof, states that we can add the same number to both sides of an equation and maintain equality. The only number we would want to add in this equation to solve it would be 1 (adding one cancels the subtracted 1); doing so cancels it on the left and gives us 27 on the right.

Answer 2

3x - 1 = 26

substitution property of equality

3x = 27

answer
3x = 27