Answer:
[tex]\begin{gathered} \text{Solution:} \\ (2.5,5.5) \end{gathered}[/tex]Step-by-step explanation:
Given the following system of equations:
[tex]\begin{gathered} x+y=8\text{ (1)} \\ x=y-3\text{ (2)} \end{gathered}[/tex]Since on equation 2, x is already isolated, substitute it into equation 1:
[tex]\begin{gathered} (y-3)+y=8 \\ \end{gathered}[/tex]Solve for y.
[tex]\begin{gathered} 2y=8+3 \\ y=\frac{11}{2}=5.5 \end{gathered}[/tex]Knowing the value of y, plug it into equation (2) and solve for x:
[tex]\begin{gathered} x=y-3 \\ x=5.5-3 \\ x=2.5 \end{gathered}[/tex]