This triangle is a special kind of isosceles triangle - it is a 45-45-90 triangle. Like other isosceles triangles, the legs of 45-45-90 triangles are congruent. However, a special property specific to 45-45-90 triangles is that their hypotenuse is equal to the product of the leg length and the square root of two.
Hyp. = leg(√2)
The hypotenuse is given for this problem, so we can plug it into the formula above to find the leg length.
26 = x(√2)
26/(√2) = x
26(√2)/(√2)(√2) = x
26(√2)/2 = x
13(√2) = x
Answer:
E. 13√2