Question

Consider the statement: 4-3+5=-6+8+4. This is a mathematically correct sentence. Is the stenence true or false? Explain how you know.

Answer 1

If 4 - 3 + 5 = -6 + 8 + 4 is a mathematically correct statement, then both sides should end up with the same number:

4 - 3 + 5 = -6 + 8 + 4     Original statement.

1 + 5 = -6 + 8 + 4     You can do this in any order, but I start by doing the 4 - 3.

6 = -6 + 8 + 4     Finish simplifying the left side.

6 = 2 + 4     Combine the -6 and 8.

6 = 6     Finish simplifying the right side.

Because both sides are equal to each other, the sentence must be true.

Therefore, the sentence is true because when simplified, the statement is 6 = 6.

Hope this helps! :)

EDIT: Just incase anyone is curious, both this way and the way the other guy used both work, as they both prove that both sides are equal.