Question

Is -7 + 9 = -9 + 7 true, false, or open?

Answer 1

false because -7+9=2 and -9+7= -2

Answer 2

False.

Explanation:

We have been given an equation
`-7+9=-9+7`. We are asked to determine whether the given equation is true or false.

We know that commutative property states that we can move around numbers while adding or multiplying them. For addition, the rule is
`a+b=b+a`.

Upon looking at our given equation, we can see that commutative property is not used properly as the signs of the numbers are not same.

On the left hand side 7 is negative and 9 is positive, while on the right hand 9 is negative and 7 is positive.

Therefore, the given equation is false.

We can verify our answer by simplifying the given equation as:

`-7+9=-9+7`

`2=-2`

Both sides are not equal, hence the equation is false.