Equivalent equations are algebraic equations that have identical solutions or roots.
To check the equivalency of both equations, we can solve both equations to check the solutions.
Equation 1: x + 1 = 4
[tex]\begin{gathered} x+1=4 \\ x=4-1 \\ x=3 \end{gathered}[/tex]Equation 2: 4x + 8 = 20
[tex]\begin{gathered} 4x+8=20 \\ 4x=20-8 \\ 4x=12 \\ x=\frac{12}{4} \\ x=3 \end{gathered}[/tex]Since the solution of both equations is x = 3, this means that both equations are equivalent.