Elimination was used to solve a system of equations.

Question

Elimination was used to solve a system of equations.

One of the intermediate steps led to the equation 7x=21

Which of the following systems could have led to this equation?

 

Is it:

 

a) 8x-y=15

    x+y=-6

 

b) 4x+3y=24

     -3x-3y=3

 

c) 7x+2y=21

    -7x-2y=21

 

d) 3x+2y=7

     2x-y=7

 

thanks

 

Answer 1

see--

   https://www.wyzant.com/resources/answers/189797/elimination_was_used_to_solve_a_system_of_equations

 

Answer 2

Hi Cory,

 

Look at each of the systems of equations and determine which one gives the intermediate equation when you subtract them.   I'll do d) for you and you can try the rest . .

 

   3x + 2y = 7

- (2x -  y = 7)

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

x  + 3y = 0  .  .   . so we know that d) is not the right answer.

 

Have fun.

 

Dan