How can you tell by just looking at the coefficients of -2x² and 2x2 that the terms will add to zero?

Answer:
Their coefficient have the same number but with opposite sign
Step-by-step explanation:
We can tell that the two coefficient will add to zero because they have the same value but opposite signs.
When two numbers are of the same value but with opposite sign, they add up to zero.
The given numbers are;
-2x² and 2x²
Coefficient is the number before the variable. Here, the variable is x,
-2x² = -2
2x² = 2
-2 + 2 = 0