Is it possible to make triangle out of 12 8 and 4?

If I have got this wrong, sorry.

What about Pythagoras Theorem.

One side is equal to the sum of the square of the other two sides.

12- 8+4.

No, because the sum of any two sides must be greater than the third side.

It will end up looking like a line (It is a line), the sum of the length of 2 sides cannot be greater than or equal to it's 3rd side (Triangle Inequality Theorem)

Notice how the two shorter sides (4+8) are exactly equal to the third side (12). So they would be right next to it forming a straight line. Except for degenerate cases, this would NOT be considered a triangle.

Answer:

No

No it's not possible because the result would be a straight line.

No.

The sum total of the lengths of two sides must always be GREATER than the length of the third side; here, you got 4 + 8 = 12. That doesn't establish a triangle.

Possible