Question

How much is `(4x^2 - 19x + 15) + (-18x^2 + 15x + 16)`?

Answer 1

`-14x^2-4x+31`
`color(white)("XXXXXXXX")`(see note below)

Explanation:

#{: (" "," " 4x^2,-19x,+15), ("+", -18x^2,+15x,+16), ("=", -14x^2,-4x,+31) :}#

Note : I removed the word "greater" from the question (which is something I normally do, since "How much greater is something + something-else ?" doesn't make any sense).
If you meant "How much greater is something than something-else ?", please re-post in a meaningful form.