Solve the System by the Substitution Method $xy=56$ $x+y=-15$ A) $\{(7,-8),(8,-7)\}$ B) $\{(-7,8),(-8,7)\}$

Multiple Choice

Solve the system by the substitution method.
- $xy=56$
$x+y=-15$

A) $\{(7,-8) ,(8,-7) \}$
B) $\{(-7,8) ,(-8,7) \}$
C) $\{(-7,-8) ,(-8,-7) \}$
D) $\{(7,8) ,(8,7) \}$