The ratio of areas of similar triangles is the square of the ratio of their linear dimensions. If the smaller triangle is 1/2 the area of the larger, then its linear dimensions are โ(1/2) those of the larger triangle.
ย smaller side length = โ(1/2) ร larger side length
ย = (โ2)/2ร36 = 18โ2 โ 25.4558