Respuesta :

Here is your graph of the system. Where they cross is the answer, which is -4. Pretty much you have to graph each equation and where they meet is the answer.

Ver imagen Аноним
and doing some vandalizing to the posted image by MathJot, check the picture below.

[tex]\bf \begin{cases} 4x-5y=20\\ 3x+y=-4 \end{cases}\\\\ -------------------------------\\\\ 4x-5y=20\implies 4x-20=5y\implies \cfrac{4x-20}{5}=y\\\\\\ \boxed{\cfrac{4x}{5}-4=y} \\\\\\ 3x+y=-4\implies \boxed{y=-4-3x}[/tex]
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