Here!
(x+4)+(x+2)+(x+5)= (x+1)+(x+1)+(x+3)+(x+3)
First you want to write the whole equation out. Make each perimeter equal to each other.
Then add both sides separately.
(x+4)+(x+2)+(x+5)
=3x+11
and
(x+1)+(x+1)+(x+3)+(x+3)
=4x+8
Now that you've simplified each side, solve like a normal equation.
3x+11 = 4x+8
-3x -3x
11 = x+8
-8 -8
3=x