The question is down below.
AB=

Step-by-step explanation:

Use the cosine identity:

cos(x) = adj/hyp.

Here, adj = 2 and and x = 50° and hyp is unknown and what we are solving for.

adj/cos(x) = hyp, 2/cos(50) = hyp.

hyp = 3.11

the balance is found at the link

step-by-step explanation:

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11