Solve the system of equations by the elimination method.
-0.8x + 0.3y = 10.7
-0.3x - 0.1y = -3.9
A)(100, 90)
B)(1, 0.9)
C)(10, 9)
D)(9, 10)

Question

Solve the system of equations by the elimination method.
-0.8x + 0.3y = 10.7 
-0.3x - 0.1y = -3.9
A)(100, 90)
B)(1, 0.9)
C)(10, 9)
D)(9, 10)

Quizplus · Accepted Answer

To eliminate y, multiply the first equation by 1 and the second equation by 3 to get:  0.8x + 0.3y = 10.7  -0.9x - 0.3y = -11.7  Add the equations:  -0.1x = -1  x = 10  Substitute x = 10 into the first equation:  0.8(10) + 0.3y = 10.7  8 + 0.3y = 10.7  0.3y = 2.7  y = 9  The solution is (10, 9).

Solve the System of Equations by the Elimination Method