A=1/2ab
Replace the variables with their value
15=1/2(3/2)b
Multiply 1/2 and 3/2

15=3/4b
Divide 3/4 on both sides
15/(3/4) is the same thing as

45/4=b
Firstly, you must find the product of 2 and x which is 2x. Add 8 and you get 2x+8.
3 feet width is added to both sides .
so the dimensions become 34 feet and 36feet
hence the fencing length required or the perimeter= 2(l+b)
= 2( 34+36)
= 2(70)
= 140feet fence
All you have to do is just put the same variable on the same side as each other.