The way that I memorised how to do sin, cos, and tan is by the following: SOH, CAH, TOA
SOH = Sin is OPPOSITE / HYPOTENUSE
CAH = Cos is ADJACENT / HYPOTENUSE
TOA = Tan is OPPOSITE / ADJACENT
For example if we were to solve question 5
Sin T = 6 root 2 / 19
Cos T = 17 / 19
Tan T = 6 root 2 / 17
Repeat the steps for question 6
For the rest of the questions (7,8,9) you have to take the information given and figure out if you should us Sin, cos, or Tan. then plug the numbers in the calculator and while doing sin ^ -1, cos ^ -1, tan ^ -1
for example on question 7, to find the angle x they have given you the hypotenuse and the adjacent side so
cos x = 9 / 18
to find x plug: cos^-1 (9/18) in the calculator