This is the Pythagorean theorem and law of sines. Let's do number 2!
Step-by-step explanation:
This is the Pythagorean theorem and law of sines. It's a 90 degree triangle, and they tell you that the other angle is 40 degrees. The total must add up to 180 in total. 90+40=130, 180-130=50. The other angle equals 50 degrees.
The law of sins is sinA/a=sinB/b=sinC/c. sin90/4=sin50/x. x=30.64177772
