AB=3,AC^2=4+x^2

BC^2=(x-3)^2+4

Two situations:

One: AB, AC is waist. Then ab = AC

That is, 9 = 4+x 2 x= radical number 5 (both positive and negative)

Two: AB, BC is waist, then AB = BC.

That is, 9 = (x-3) 2+4 and x= plus or minus 5+3.