Which of the following would not be the result of a substitution in the following system? 2x + y = 7y - x= 1a. 7 - 2x- x = 1b. 2x + x + 1 = 7c. 2(y + 1) + y = 7​

The correct option is:

C.

To find which of the given options are not the result of a substitution in the given system, we need to isolate the variable in function of the other variable, and then substitute it.

So, substituting and discarding, we have:

- First equation:

Isolating "y", we have:

Then, substituting it into the second equation, we have:

We have that it's a result of a substitutiong in the following system (option A)

- Second equation:

Isolating "y", we have:

Then, substituting it into the first equation, we have:

Have a nice day!

Option C.

Step-by-step explanation:

A) The result of the substitution shown in Option A is obtained by solving for y from the first equation and substituting into the second equation:

Therefore, this is a result of a substitution in the given system.

B) The result of the substitution shown in Option B is obtained by solving for y from the second equation and substituting into the first equation:

Therefore, this is a result of a substitution in the given system.

C) The result of the substitution shown in Option C is not  a result of a substitution in the given system, because if you solve for x from the second equation and substitute into the first one, you get:

A

Step-by-step explanation:

y-x=1 so to solve for x

-x = -y + 1

x = (y - 1) so A is incorrect because it substitutes (y +1) for x