The perimeter of a room is 16.8cm. If the width is (X - 3)cm, find it's length in terms of X

Let's start by using the formula for the perimeter of a rectangle:

Perimeter = 2(length + width)

We can plug in what we know and simplify:

16.8cm = 2(length + (X - 3)cm)

Divide both sides by 2:

8.4cm = length + (X - 3)cm

Subtract (X - 3)cm from both sides:

8.4cm - (X - 3)cm = length

Simplify:

11.4cm - X = length

So the length of the room in terms of X is 11.4cm - X.

To find the length of the room in terms of X, we need to use the formula for the perimeter of a rectangle.

The formula for the perimeter of a rectangle is: P = 2l + 2w, where P is the perimeter, l is the length, and w is the width.

Given that the perimeter of the room is 16.8cm and the width is (X - 3)cm, we can substitute these values into the formula.

16.8 = 2l + 2(X - 3)

Now, let's solve for the length.

16.8 = 2l + 2X - 6

To isolate the length term, we can simplify the equation.

16.8 + 6 = 2l + 2X

22.8 = 2l + 2X

Next, we can divide both sides of the equation by 2 to solve for l.

22.8/2 = (2l + 2X)/2

11.4 = l + X

Finally, we can subtract X from both sides of the equation to isolate the length.

11.4 - X = l

So, the length of the room in terms of X is (11.4 - X) cm.