The value of x in this 45°-45°-90° triangle is x√2.
In a 45°-45°-90° triangle, the sides are in the ratio 1:1:√2.
This means that the length of the hypotenuse is √2 times the length of a leg.
If x represents the length of one leg, then the length of the hypotenuse is x√2.
Therefore, the value of x in this 45°-45°-90° triangle is x√2.