Question 28332
The two isosceles triangles are "similar" so their sides are "proportional"
Find the scale factor by dividing the known length of one side of the larger triangle by the known length of a "corresponding" side of the smaller triangle.

Scale factor is: 8"/2" = 4

Multiply the length of the base of the smaller triangle by the scale factor of 4 to find the unknown length of the base of the larger triangle.

Base of smaller triangle = 3"
Base of larger triangle = 4 X 3" = 12"