Answer:
46
Step-by-step explanation:
I found the angle by taking the opposite side of the angle, 38, and dividing it by the hypotenuse, 53.
Then I used the inverse sine function on 38/53 to get the angle 45.81, which I rounded to 46.
There is no real shortcut in learning integration formulas. You should take time learning and understanding how the formulas are derived until you are familiar with the formulas and you can easily recall the formulas. Hope this answers the question.