Question

What is the solution to the system of equations shown below?S 3x + y = 61ly= -4x + 5)

Answer 1

Let us write out the equation,

`\begin{gathered} 3x+y=6\ldots\ldots\text{.}.1 \\ y=-4x+5\ldots\ldots2 \end{gathered}`

We will apply the method of substitution to resolve the equations.

Let us make y the subject of the formula in equation 1,

`\begin{gathered} 3x+y=6 \\ y=6-3x\ldots\ldots\ldots.3 \end{gathered}`

Let us substitute the value of y=6-3x into equation 2, and solve for x

`\begin{gathered} 6-3x=-4x+5 \\ \text{collect like terms} \\ -3x+4x=5-6 \\ x=-1 \end{gathered}`

Let us solve for y by substituting the value of x= -1 into equation 3.

`\begin{gathered} y=6-3x \\ y=6-3(-1) \\ y=6+3 \\ y=9 \end{gathered}`

Hence, the solution of the equation is (x,y)= (-1,9).

The correct option is option 1.