Question

the system by substitution.
$-7x - 10y = 40$
$x = -2y$

Explanation:

Step1: Substitute $x=-2y$ into first equation

$-7(-2y) - 10y = 40$

Step2: Simplify left-hand side

$14y - 10y = 40$
$4y = 40$

Step3: Solve for $y$

$y = \frac{40}{4} = 10$

Step4: Substitute $y=10$ into $x=-2y$

$x = -2(10) = -20$

Answer:

$x=-20$, $y=10$