Answer:
Step-by-step explanation:
let length of small triangle=y
2(x+y)=21
x+y=21/2=10.5
also y=2x
as you can see from vertical rectangle.
x+2x=10.5
3x=10.5
x=10.5/3=3.5
y=2×3.5=7
length of large rectangle=x+y=10.5 cm
width of large rectangle=2x=2×3.5=7 cm
perimeter of large rectangle=2(10.5+7)=2×17.5=35 cm
