What is the first step in solving the following system of equations? 3 x + y = 23. 8 x + 2 y = 23. Substitute the value of y from one equation into the other equation. Solve the first equation for y. Subtract the second equation from the first equation. Substitute the value of x from one equation into the other equation.

B

Step-by-step explanation:

Our system of equations is:

3x + y = 23

8x + 2y = 23

If we want to use substitution, that means that we essentially want to manipulate one of the two equations so that one variable (like y) is written in terms of the other (like x), and then substitute that expression into the second equation so that we have one variable and one equation and we can easily solve from there.

So the first thing to be done is to write one of the variables in terms of the other. It would be easiest to do it with the first equation and write y in terms of x - in other words, "solve the first equation for y".

The answer is B.

Second option:

Solve the first equation for y.

Step-by-step explanation:

3 x + y = 23 (1)

8 x + 2 y = 23 (2)

To solve this system, first step is to make y the subject from (1)

y = 23 - 3x