Which expression is equal to x−4x−7+x2−2x+3x−7 ?
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Answer:
It's the first one.
Step-by-step explanation:
Collect like terms.
x-4+x^2-2x+3
---------------------------
x-7
take x and (-2x): this equals -x
Take (-4) and 3: this equals (-1)
reorder the terms
-x-1+x^2
------------
x-7
Use the commutative property
x^2-x-1
------------
x-7