Answer:
Area=3x+12
Perimeter=6x+30
Step-by-step explanation:
Area of the rectangle = width*length
Perimeter of the rectangle = 2width+2length
Width=3
Length=(x+4)
A=3(x+4)
A=3x+12
P=2(3)+2(3x+12)
P=6+6x+24
P=6x+30