(a^2)/A = (b^2)/B = (c^2)/C
a^2=b^2+c^2-2bcCOSA
Okay so, it's been a while, but...
You're gonna do this twice.
First
Angle A = 90
Angle B = ?
Angle C = ?
Side A = 16^2
Side B = ?
Side C = ?
You need to determine another side or another angle in the larger triangle to continue.