Solved by substitution for
y=x-6
y=8x+1

Here is your system of equations:

When solving a system of equations, you can either eliminate or substitute, however, I will be substituting since that's what the question is asking.

In the first equation, if y is equal to x - 6, I can substitute it with the y in the second equation with 8x + 1.

Here is your new equation:

Since you have variables on both sides, you have to cancel it on either side. In the equation on the left, the variable is x. To cancel it out, you have to do the opposite of it, which is -x, or negative x. That means you have to subtract x to both equations.

Now you have one variable and two regular integers. You have to leave the variable x alone to find its value. Along with it is +1, or positive 1. To remove it, you have to do the opposite of it, which is -1 or subtract 1.

Now you need x to stay alone, so divide both sides by 7.

Remember:

NEGATIVES

POSITIVES

Now that you have the value of x, you can substitute it with the x in one of the equations.

Subtract -1 by 6:

That means y is equal to -7.

Your answer is (-1, -7).

its definatley   this on your answer choice?

13

step-by-step explanation:

divide the cost of the total of sodas you bought by the cost of one soda, for example:

$24.57 divided by $1.89 is 13 which means you bought 13 sodas