Bonjour,
4+x+1 +3x-2 = 4x +3
rectangle:
2( 3x-5 +2x-1)=
2( 5x -6)=
10x -12
4x+3 = 10x-12
3+12 = 10x -4x
15 = 6x
x= 15/6 =2,5
