Using the Soh, Cah or Toa I need to find x which is the adjacent angle, I have 4.200 as the opposite angle and need to find the hypotenuse. I only have one known and need to find x. However I do have all the internal angles as 90, 25 & 65. Can anyone help?

THe opposite side you mea, not the opposite angle?

You need to find the hypotenuse, so looks for the part of SOH CAH TOA that has the opposite and the hypotenuse in it.

this is SOH, so you need to use sin(angle) = opposite/hypotenuse.

Rearranging, we find that hypotenuse = opposite/sin(angle)

now you need to use (for angle) the angle that is opposite the "opposite" side. Plug in your values and away we go!