Problem 4: Find the perimeter of the triangle below:

Subtract $x$ from both sides:

Add 4 to both sides:

Side 1: $2x - 4 = 2(12) - 4 = 24 - 4 = 20 \text{ cm}$
Side 2: $x + 8 = 12 + 8 = 20 \text{ cm}$
Side 3: $3x + 11 = 3(12) + 11 = 36 + 11 = 47 \text{ cm}$

The perimeter is the sum of all side lengths.

The perimeter of the triangle is $\boxed{87 \text{ cm}}$.

: The figure below is a rectangle. Study it and answer the questions that follow.

The question is incomplete as it does not specify what to find. We will assume the questions are to find the value of $x$, the dimensions of the rectangle, its perimeter, and its area.

In a rectangle, opposite sides are equal in length. From the tick marks, the top side is equal to the bottom side.
So, $5x + 5 = x + 27$.

Subtract $x$ from both sides:

Subtract 5 from both sides:

Divide by 4:

Length ($L$): $5x + 5 = 5(5.5) + 5 = 27.5 + 5 = 32.5 \text{ cm}$
(Check with bottom side: $x + 27 = 5.5 + 27 = 32.5 \text{ cm}$)
Width ($W$): $2x = 2(5.5) = 11 \text{ cm}$

For the rectangle:
Value of $x$: $\boxed{5.5}$
Length: $\boxed{32.5 \text{ cm}}$
Width: $\boxed{11 \text{ cm}}$
Perimeter: $\boxed{87 \text{ cm}}$
Area: $\boxed{357.5 \text{ cm}^2}$