Question

Sydney is cutting the crust from the edges of her sandwich. The dimensions, in centimeters, of the sandwich is shown.

A rectangle labeled sandwich. The right side is labeled 2 x squared + 9. The bottom side is labeled 2 x squared + 8.
Which expression represents the total perimeter of her sandwich, and if x = 1.2, what is the approximate length of the crust?

Answer 1

Given:

A rectangle based sandwich.

Right side is $2x^2+9$.

Left side is $2x^2+8$

To find:

The expression to represent the total perimeter of the sandwich.

And approximate length of crust if $x=1.2$.

Solution:

As per the property of rectangles, left and right sides are equal.

And bottom and top sides are equal to each other.

Perimeter of a rectangle = $2\times (Length + Breadth)$

$\Rightarrow 2\times (2x^2+8+2x^2+9)\\\Rightarrow \bold{8x^2+34}$

So the perimeter of the rectangular sandwich is:

$8x^2+34$

Length of the crust cut from the sandwich will actually be equal to the perimeter of the sandwich itself because the crust is cut from the edges of the rectangular sandwich only.

Putting $x=1.2$ in the above equation of the perimeter:

$\Rightarrow 8(1.2)^2+34\\\Rightarrow \bold{45.52}$