Surface Area of a Cuboid: Calculate The Missing Side based on the formula

Look at the cuboid of the figure.

Its surface area is 122 cm².

What is the width of the cuboid?

To solve the problem, let's recall the formula for calculating the surface area of a box:

(width*length + height*width + height*length) *2

Let's substitute the known values into the formula, and we'll denote the missing side as X:

2*(3*7+7*X+3*X) = 122

2*(21+7x+3x) = 122

2(21+10x) = 122

Let's expand the parentheses:

42+20x=122

Let's move terms:

20x=122-42

20x=80

Let's simplify:

x=4

And that's the solution!

4 cm

The surface area of a cube is 24 cm².

How long are the sides of the cube?

2

Look at the cuboid in the figure below.

Its surface area 752 cm².

Calculate X.

10 cm

Given the cuboid of the figure:

Given that the marked face is a square whose sides are 7 cm

Find the length of the cuboid, given that its surface area is 406 cm².

11 cm

Look at the cuboid of the figure below.

Its surface area is 124 cm².

Calculate the length of the cuboid.

$9$ cm

The area of the cube is 486.

Calculate the length of the side of the cube and its volume.

$a=9,V=729$

Below is an unfolded cuboid.

The surface of the cuboid is 172 cm².

Calculate X.

8 cm

The surface area of the rectangular prism in the diagram is $4x^2+24x$.

Calculate the height of the rectangular prism.

$4$ cm

The surface area of a cube is 24 cm². How long is the cube's side?

$2$

A cuboid has the following dimensions:

$4\times3x\times2y$

Its surface area is:

$66x+56$

What is the value of $y$?

$3.5$ cm