Help me with these three quesions for brainiest:)

See below.

Step-by-step explanation:

1) Two equations are equivalent if they have the same solutions.

2) As long as two expressions and are equal, so , adding the same value for both sides still makes the equation true, so

is true.

3) As long as two expressions and are equal, so , subtracting the same value for both sides still makes the equation true, so

is true.

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step-by-step explanation: