\[\boxed{\text{338\ (338).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[3x^{2} + 10x - 5 =\]
\[= 7x^{2} - 4x^{2} - 3x + 13x - 5 =\]
\[= \left( 7x^{2} - 3x \right) - \left( 4x^{2} - 13x + 5 \right).\ \]