Solución
$$\mathop {\lim }\limits_{x \to - 9} \left( {xf\left( x \right) + 2g\left( x \right)} \right) = \left( {\mathop {\lim }\limits_{x \to - 9} x} \right)\left( {\mathop {\lim }\limits_{x \to - 9} f\left( x \right)} \right) + 2\mathop {\lim }\limits_{x \to - 9} g\left( x \right) = - 46$$