Answer:

Step-by-step explanation:
Given the system of two equations:

Add these two equations (left side add to left side and right side add to right side):

Substitute
into the first equation:

The opposite of something means to change this signed that is with the number.
If it is a positive number, the opposite would be negative.
So in this example, if it's the opposite of positive 5, that is -5. The opposite of -5 would be positive 5.
The equation that shows this correctly would be D.
Answer:
Step-by-step explanation:
its the size of my nut$. hope this helps!
Correct, the answer is B.