Evaluate (2x^2+7x)+(-x^2+10x+3)

$(2 x^{2} + 7 x) + (- x^{2} + 10 x + 3)$

Remove parentheses.

$2 x^{2} + 7 x - x^{2} + 10 x + 3$

Subtract $x^{2}$ from $2 x^{2}$ .

$x^{2} + 7 x + 10 x + 3$

Add $7 x$ and $10 x$ .

$x^{2} + 17 x + 3$