Answer:
1) Let's consider the first case with the number 0 the oppose is also 0 and we have that 0-0=0 so then applies
2) Now let's consider any real number a no matter positive or negative we will have that:
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Or in the other case:
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So then we can conclude that the expression is a general rule and is true
Step-by-step explanation:
For this case we can verify if the following expression is true or false:
The sum of x and it’s opposite is always zero?
If we want to proof this we need to show that for any number is true.
1) Let's consider the first case with the number 0 the oppose is also 0 and we have that 0-0=0 so then applies
2) Now let's consider any real number a no matter positive or negative we will have that:

Or in the other case:
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So then we can conclude that the expression is a general rule and is true
Answer:
350
Step-by-step explanation:
In this case you would round up, to the nearest multiple of 10. Since 348 is closer to 350 than it is to 340, the answer is 350.