Question

solve. \

$$\begin{cases} y = x - 7 \\\\ 5x + 2y = 7 \\end{cases}$$

use the substitution method. \\( \circ\\ (-1, -8) \\) \\( \circ\\ (3, -4) \\) \\( \circ\\ (7, 0) \\) \\( \circ\\ (0, -7) \\)

Explanation:

Step1: Substitute $y=x-7$ into the second equation

$5x + 2(x - 7) = 7$

Step2: Expand and simplify the equation

$5x + 2x - 14 = 7$
$7x - 14 = 7$

Step3: Solve for $x$

$7x = 7 + 14$
$7x = 21$
$x = \frac{21}{7} = 3$

Step4: Substitute $x=3$ into $y=x-7$

$y = 3 - 7 = -4$

Answer:

B. $(3, - 4)$