#### Answer

(-14/3, -35/3)
Please see the graph.

#### Work Step by Step

$y = -2x-21$
$y= x-7$
$-2x-21 = x-7$
$-2x-21 + 21-x = x-7+21-x$
$-3x = 14$
$-3x/-3 = 14/-3$
$x = -14/3$
$y = x-7$
$y = -14/3 - 7$
$y = -14/3-21/3$
$y = -35/3$
The graph was created using graphing software.
Red line: $y=-2x-21$
Blue line: $y=x-7$