Question

9) Solve by using substitution and state the solution as an ordered pair. Show all of the steps used to determine the solution. y=x+3 2x-y=4

Answer 1

The solution to th system of linear equations shown as an ordered pair is (7,10)

Here, we want to solve the system of linear equations by substtitution

From the first equation, we alraedy have an expression for y as;

`y\text{ = x + 3}`

Substitute this for y in the second equation. We have;

`\begin{gathered} 2x-(x+3)\text{ = 4} \\ \\ 2x\text{ - x - 3 = 4} \\ x\text{ -3 = 4} \\ x\text{ = 4+3 } \\ x\text{ = 7} \end{gathered}`

From the first equation, recall we have an equation for y. Simply plug in the value of x in that equation to get the value of y

Mathematically, that would be;

`\begin{gathered} y\text{ = 7 + 3} \\ \\ y\text{ = 10} \end{gathered}`