Solve the system of equations by using the addition method.
-Solve the system by the addition method.
$7.7 x + 7.1 y = - 3.5$
$- 7.1 x - 7.3 y = 8.5$
A) $\{ ( 6 , - 7 ) \}$
B) $\{ ( 13.3 , - 14.1 ) \}$
C) $\{ ( - 1.1,0.7 ) \}$
D) $\{ ( 13.1 , - 14.7 ) \}$

Question

Quizplus · Accepted Answer

Explanation:Add the two equations to eliminate the x-variable.$7.7 x + 7.1 y = - 3.5$$- 7.1 x - 7.3 y = 8.5$--------------------------------$0.6y = 5$$y = 5/0.6$$y = 8.33$Substitute the value of y into one of the original equations to solve for x.$7.7 x + 7.1 (8.33) = - 3.5$$7.7 x + 59.463 = - 3.5$$7.7 x = - 62.963$$x = - 62.963/7.7$$x = - 8.18$Therefore, the solution to the system of equations is $\{ ( - 8.18 , 8.33 ) \}$.

Solve the System of Equations by Using the Addition Method 7.7x+7.1y=−3.57.7 x + 7.1 y = - 3.57.7x+7.1y=−3.5

Solve the System of Equations by Using the Addition Method $7.7 x + 7.1 y = - 3.5$