5. (10 points) As shown in the figure, it is a rectangular paper sheet with a grid of $3 \times 4$. The front side of the rectangular paper sheet is gray, and the back side is red. The grid consists of identical small squares. Cut the rectangle along the grid lines into two cards of the same shape. If the shape and the color on the front and back sides are the same, they are considered the same type of card. Therefore, the number of different types of cards that can be cut out is $\qquad$.
【Analysis】First analyze the subtraction to the left, then derive the cutting methods to the right based on the left-right symmetry, subtract the overlapping cutting methods, and thus obtain the total number of different cutting methods.

【Solution】Solution: First consider cutting from the front, the middle thick line must be cut open. After cutting, there are three choices from point 1, up, left, and right;
1. Up:
2. Left:
Cut to point 3, there are 3 choices, up, left, and down,
(1) Up (black line):
, the red line is the symmetrical situation to the black line, but the shape cut along the red line is the same as the black line after rotation, which belongs to the 2nd type;
(2) Left:
, the shape cut along the red line is different from the black line after rotation, these are two different types, belonging to the 3rd and 4th types;
(3) Down:

Cut down to point 6, there are two choices, left and down,
(1) Left:
, the shape cut along the red line is different from the black line after rotation, these are two different types,
belonging to the 5th and 6th types;
(2) Down:
, the shape cut along the red line is different from the black line after rotation, these are two different types,
belonging to the 7th and 8th types;
In summary, there are a total of 8 types.
Therefore, the answer is: 8.