Asquare tabletop has an area of
(9x2 - 90x+225) cm². the dimensions
of the tabletop have the form cx - di
where cand d are whole numbers. write
an expression for the perimeter of the
tabletop. then find the perimeter when
x= 25 centimeters.

s = 3x - 15 is the required expression for perimeter of table top

Perimeter of square tabletop is 240 cm

Solution:

A square tabletop has an area given as:

The dimensions  of the tabletop have the form cx - di  ,where cand d are whole numbers

To find perimeter of tabletop when x = 25 centimeters

Let us first find the length of each side of square

Given area is:

We know that,

Therefore,

Taking square root on both sides,

s = 3x - 15

The above expression is the required expression for perimeter of table top

To find perimeter when x = 25 centimeter

The perimeter of square is given as:

perimeter = 4(3x - 15)

Substitute x = 25

perimeter = 4(3(25) - 15)

perimeter = 4(60) = 240

Therefore perimeter of square tabletop is 240 cm

Mass of gold bar=13.896