Question

Find the solution to the system of equations given below x=-4 5x+4y=-16

Answer 1

We have the following system of equations:

`\begin{gathered} x=-4\ldots(A) \\ 5x+4y=-16\ldots(B) \end{gathered}`

Solving by substitution method.

If we substitute equation A into equation B, we get

`5(-4)+4y=-16`

since 5(-4)= -20, we have

`-20+4y=-16`

If we move -20 to the right hand side as +20, we obtain

`\begin{gathered} 4y=-16+20 \\ \end{gathered}`

since -16+20=20-16 = 4, we get

`4y=4`

and finally, y is equal to

`\begin{gathered} y=(4)/(4) \\ y=1 \end{gathered}`

Since equation A tells us that x=-4, the solution of the system is

`\begin{gathered} x=-4 \\ y=1 \end{gathered}`