The reason why I am saying that x is 5 is because by using the Pythagoras Theorem. According to that law, it states that Hypotenuse^2 = base^2 + altitude^2..
So with that formula, I applied the probable answer which can be possible.
=) 3^2 + 4^2
=) 9 + 16
=) 25
Therefore the square root of 25 is the answer.. That is five..
You can put this solution on YOUR website! The largest the third side could be has to be less than 7. If it is larger than 7 then the other two sides cannot join each other. If it is 7 then you have a line (with a 3 and a 4 on top of it) rather than a triangle.
The smallest that the third side could be is larger than 1. If it is smaller than one then it cannot join onto the side of length 3 to make a total length of 4. Again if it is 1 you have a line (4 long with the 1 and 3 on top of it) rather than a triangle.
So x can be any size between 1 and 7 not including 1 or 7
i.e. 1 < x < 7