<h3>x²+5x+3+2x²+10x15 =0</h3><h3>x²+2x²+5x+10x+3+15=0</h3><h3>3x²+15x+18=0</h3><h3>3(x²+5x+6) =0 because 3 is common factor</h3><h3>3(x²+3x+2x+6) spill the middle term</h3><h3>3(x(x+3)+2(x+3) take the common factor from term</h3><h3>3(x+2) (x+3)</h3><h3>answer is 3(x+2) (x+3)</h3>