Question

Can someone answer for me please, if you're great at math.

Answer 1

Assuming that c is the length of AB (as is usually the case in the angle-side notation for triangles):
If sin(35) = 12/c, we can transform by multiplying both sides by c, and dividing both by sin(35) to get
c = 12/sin(35)
Evaluating using a calculator gives 20.92 units.