Question

Madison created this solved this proof. She wants to know if she solved it correctly. After looking at the proof, decide whether she solved the proof correctly. If she did not explain why it is incorrect and correct it.

Answer 1

given. Distributive property. Simplify. Addition property of equality

DIVISION PROPERTY OF EQUALITY but not multiplication property of equality.

Answer 2

Madison's proof is pretty good. She gets the right answer as we can verify:

4(5(-11) + 7) - 3(-11) = 4(-48) + 33 = -192 + 33 = -159

3(4(-11) - 9) = 3(-53) = -159, good

The only problem is her justification to go from 5n + 28 = -27 to the next line. She adds -28 to both sides and gets 5n = - 55. That should be labeled "Addition Property of Equality" like the line before.