Solve the following system of equations with the substitution method:
${\begin{cases} x + 3 y = - 1 \\ - 3 x - 4 y = 5 \end{cases}$
Answer: $(x, y) =$
Preview $x$ :
Preview $y$ :
Enter your answers as integers or as reduced fractions in the form A/B.

Answer

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Answer

$(x, y) = (- \frac{11}{5}, \frac{2}{5})$

Steps

Step 1 ：First, we solve the first equation for x: $x = - 3 y - 1$

Step 2 ：Next, we substitute this expression for x into the second equation: $- 3 (- 3 y - 1) - 4 y = 5$

Step 3 ：Solving this equation gives us $y = \frac{2}{5}$

Step 4 ：Substituting $y = \frac{2}{5}$ back into the first equation gives us $x = - \frac{11}{5}$

Step 5 ： $(x, y) = (- \frac{11}{5}, \frac{2}{5})$