Question

The solution of the system of equations. 7x+14y=-218x+2y=4Solution: ( _,_)

Answer 1

Given the following System of equations:

`\begin{cases}7x+14y=-21 \\ 8x+2y=4\end{cases}`

You can solve it using the Elimination method, as following:

1. You can multiply the second equation by -7.

2. Add the equations and solve for "x".

Then:

`\begin{gathered} \begin{cases}7x+14y=-21 \\ -56x-14y=-28\end{cases} \\ ------------ \\ -49x=-49 \\ \\ x=(-49)/(-49) \\ \\ x=1 \end{gathered}`

3. Knowing the value of the variable "x", you can substitute it into any original equation and solve for the variable "y" in order to find its value. This is:

`\begin{gathered} 8x+2y=4 \\ 8(1)+2y=4 \\ 2y=4-8 \\ 2y=-4 \\ \\ y=(-4)/(2) \\ \\ y=-2 \end{gathered}`

Then, the solution is:

`(1,-2)`