Please help I don’t understand

Answer:
Step-by-step explanation:
so many isosceles triangles
y = 4 .. just by inspection.. we can see
SOH CAH TOA <= ask me about this if you don't get it
Cos(x) = Adj / Hyp
we don't know the Hyp this time so solve for that
Hyp = Adj / Cos(x)
Hyp = 4 / Cos(45)
Hyp = 4 / [tex]\sqrt{2}/2[/tex]
maybe you know.. but i'll just remind you to bring the fraction up from the denominator... invert and multiply
Hyp = 4 * 2/[tex]\sqrt{2}[/tex]
Hyp = 8/ [tex]\sqrt{2}[/tex]
also we are supposed to write as a decimal rounded to the nearest 10th
Hyp = 5.66