Question

Im getting an answer that i dont know if its correct so pls help me

Answer 1

$\bf \begin{array}{llll} 18x-y=24&\implies &\quad 18x-y=24\\ 9x+4y=-15&\boxed{\times -2}\implies &-18x-8y=30\\ &&--------\\ &&\qquad 0-9y=54 \end{array}\\\\ -----------------------------\\\\ -9y=54\implies y=\cfrac{54}{-9}\implies \boxed{y=-6} \\\\\\ \textit{now, let's use that "y" in the first equation} \\\\\\ 18x-(-6)=24\implies 18x+6=24\implies 18x=18\implies \boxed{x=1}$