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A system of equations and its solution are given below.

System A:
5x - y = -11
3x - 2y = -8
Solution: (-2,1)

To get system B below, the second equation in system A was replaced by the sum of that equation and the first equation in system A multiplied by -2.

System B:
5x - y = -11
?

A.
The second equation in system B is 7x = 30. The solution to system B will be the same as the solution to system A.
B.
The second equation in system B is 7x = 30. The solution to system B will not be the same as the solution to system A.
C.
The second equation in system B is -7x = 14. The solution to system B will be the same as the solution to system A.
D.
The second equation in system B is -7x = 14. The solution to system B will not be the same as the solution to system A.

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jaimitovarela56 jaimitovarela56 · Answer 1 · 2019-04-16T17:56:06+02:00

I think is b not sure

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lublana lublana · Answer 2 · 2019-07-04T11:49:10+02:00

Answer:

C. The second equation in system B is [tex]-7x=14[/tex] .The solution to system B will be the same as the solution to system A.

Step-by-step explanation:

Given

System A:

[tex]5x-y=-11[/tex]

[tex]3x-2y=-8[/tex]

System B:

[tex]5x-y=-11[/tex]

When we multiply I equation of system A by -2 then we get new equation

[tex]-10x+2y=22[/tex] ( III equation )

Adding equation II of system A and eqaution III then we get

[tex]-7x=14[/tex]

Hence, II equation of system B

[tex]-7x=14[/tex]

By division property of equality

[tex]x=\frac{14}{-7}[/tex]

x=-2

Substitute the value of x=-2 in equation I of system B then we get

[tex]5(-2)-y=-11[/tex]

-10-y=-11

By simplification

[tex]-y=-11+10[/tex]=-1

y=1

By simplification

Therefore, the solution of system B is (-2,1).

Hence, option C is correct .

C. The second equation in system B is -7x=14 . The solution to system B will be the same as the solution to system A.