Answer: -10p²
This is the same as saying -10p^2
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Explanation:
Both terms 8p² and -18p² are like terms.
We combine them in much the same way as 8-18 = -10, just with a p² attached to everything.
So 8p² - 18p² = (8-18)p² = -10p²
The coefficient -10 is negative because we're subtracting small minus big. If it was the other way around, then we'd get a positive value.
