Answer:
[tex]4.6\ \text{cm}[/tex]
Step-by-step explanation:
Perimeter of the pentagon = 20.5 cm
Length of 4 sides = [tex]x[/tex]
Length of the other side = 2.1 cm
Perimeter of the pentagon will be
[tex]x+x+x+x+2.1=20.5\\\Rightarrow 4x+2.1=20.5\\\Rightarrow 4x=20.5-2.1\\\Rightarrow 4x=18.4\\\Rightarrow x=\dfrac{18.4}{4}\\\Rightarrow x=4.6\ \text{cm}[/tex]
The value of [tex]x[/tex] is [tex]4.6\ \text{cm}[/tex].
