Evaluate: -9x^2-4+10x+11x^2-15x

Expression: $-9x^{2}-4+10x+11x^{2}-15x$

Group like terms

$=-9x^{2}+11x^{2}+10x-15x-4$

Add similar elements: $ -9x^{2}+11x^{2}=2x^{2}$

$=2x^{2}+10x-15x-4$

Add similar elements: $ 10x-15x=-5x$

$=2x^{2}-5x-4$