574.54-396.23= 178.31
So Y=178.31
Answer: $14.40
10% of $18 = $1.80 (just divide it by 10)
$1.80 x 2 = $3.60
20% of $18 = $3.60
since it’s a discount, you subtract from the original price so:
$18 - $3.60 = $14.40
Let the width of the rectangle be 'w'
According to the question length of the rectangle (l) is three feet more than twice it's width;
l = (2w + 3) ft
Perimeter of rectangle = 78 ft
Formula of perimeter of rectangle = 2(Length + Width)
So,

Width of the rectangle (w) = 12 ft
where is the rest of the question?
is that it?