Find the Cuboid Length: Solving Volume = 12X with Height 4cm

Question

Given the height of the cuboid 4 cm

width of the cuboid is equal to X

length of the cuboid is greater by 2 than its width

The volume of the cuboid is equal to 12X

Calculate the length of the cuboid

444XXX

Video Solution

Solution Steps

00:00 Calculate the length of the box
00:03 Use the formula for calculating box volume
00:07 Width times height times length
00:14 Substitute appropriate values and solve for X
00:27 Arrange the equation
00:34 Open parentheses properly, multiply each factor
00:40 Isolate X
01:06 This is the value of X
01:18 Substitute the X value we found to find the box length
01:21 And this is the solution to the problem

Step-by-Step Solution

To solve this problem, we follow these steps:

  • Step 1: Use the cuboid volume formula Volume=length×width×height\text{Volume} = \text{length} \times \text{width} \times \text{height}.
  • Step 2: Substitute the expressions for length (X+2)(X + 2), width XX, and height 44 into the formula.
  • Step 3: Equate the expression to the given volume 12X12X and solve for XX.
  • Step 4: Once XX is determined, calculate the length as X+2X + 2.

Now, let's work through each step:

Step 1: The formula for volume is:

Volume=length×width×height\text{Volume} = \text{length} \times \text{width} \times \text{height}

Step 2: Substitute the given values:

Volume=(X+2)×X×4=12X\text{Volume} = (X + 2) \times X \times 4 = 12X

Step 3: Solve for XX:

Expanding the left side, we have:

(X2+2X)×4=12X(X^2 + 2X) \times 4 = 12X

This simplifies to:

4X2+8X=12X4X^2 + 8X = 12X

Rearranging gives:

4X2+8X12X=04X^2 + 8X - 12X = 0

4X24X=04X^2 - 4X = 0

Factor out 4X4X:

4X(X1)=04X(X - 1) = 0

Thus, 4X=04X = 0 or X1=0X - 1 = 0. The only meaningful solution (since XX can't be zero) is:

X=1X = 1

Step 4: Calculate the length:

The length is X+2=1+2=3X + 2 = 1 + 2 = 3 cm.

Therefore, the length of the cuboid is 3 cm3 \text{ cm}.

Answer

3 cm