add or subtract to simplify: (4x² + x) - (x² + 2x)

Explanation:

Step1: Remove parentheses

$$(4x^{2}+x)-(x^{2}+2x)=4x^{2}+x - x^{2}-2x$$

Step2: Combine like terms

$$4x^{2}-x^{2}+x - 2x=(4 - 1)x^{2}+(1 - 2)x=3x^{2}-x$$

Answer:

$3x^{2}-x$ (the second option)