A student took a system of equations, multiplied the first equation 2 by 3 and the second equation by , then added the results together. Based on this, she concluded that there were no solutions. Which system of equations could she have started with?

A. -2x+4y=4
-3x+6y=6
B. 3x+y=12
-3x+6y=6
C.3x+6y=9
-2x-4y=4
D.2x-4y=6
-3x+6y=9

Respuesta :

Answer:

C)3x+6y=9

-2x-4y=4

Step-by-step explanation:

A student took a system of equations, multiplied the first equation 2 by 3 and the second equation by , then added the results together.

Lets check with each option

We multiply the first equation by 2  and second equation by 3 and add it.

When both x  and y terms gets cancelled then we can say there were no solutions.

A) -2x+4y=4

-3x+6y=6

Equation becomes

-4x + 8y = 8

-9x + 18y = 18

------------------------

-13x + 26y = 26

B) 3x+y=12

-3x+6y=6

Multiply first equation by 2  and second equation by 3

6x + 2y = 24

-9x + 18x = 18

------------------------

-3x + 20y = 42

C)3x+6y=9

-2x-4y=4

Multiply first equation by 2  and second equation by 3

6x + 12y = 18

-6x - 12y = 12

---------------------------

          0 = 30

Both x  and y terms becomes 0. Hence there is no solution for these system of equations.