Hello from MrBillDoesMath!
Answer:
2cos(20) is the exact answer
(1.88 is an approximation)
Discussion:
From trigonometry
cos(20) = side adjacent angle / hypotenuse
= ? / 2
Multiply both sides by 2 to get
2 cos(20) = ? =>
? = 2 (0.9397) approximately (done via calculator)
? = 1.88
Thank you,
MrB