Question

The substitution method: Solve for x in the second equation and substitute it into the first equation. The result is .

Answer 1

Answer: solve for c in a second equation and substitute: correct is 2(-3+2y) +5y= -6. 100% correct.

Explanation:

Answer 2

Suppose you have the following system of linear equation:

`\left \{ {{(1) \ ax+by=c} \atop {(2) \ dx+ey=f}} \right.`

According to the statement above, first we need to solve for x in the second equation:

`dx+ey=f \\ \\ \therefore x=(f-ey)/(d)`

Next we need to substitute x into the first equation, so:

`a\left((f-ey)/(d)\right)+by=c`

So, the conclusion is that from this last equation the result we can get is y. Then, by substituting the value of y in the first or second equation we can get x.