Solve the system by the addition method. 3x + 7y = -20
-3x + 6y = -6
A) (-9, 1)
B) (5, -5)
C) (-2, -2)
D) (4, 1)

Question

Quizplus · Accepted Answer

Adding the two equations directly cancels out the x terms: $3x + 7y + (-3x + 6y) = -20 + (-6)$, simplifying to $13y = -26$, which gives $y = -2$. Substituting $y = -2$ into the first equation: $3x + 7(-2) = -20$, simplifying to $3x - 14 = -20$, which gives $3x = -6$, and thus $x = -2$. Therefore, the solution is $(-2, -2)$.

Solve the System by the Addition Method