Answer: The correct answer is 5.
Solution:het
Given : In image attached
a =?, b = 6, c = 4 , A = [tex]55^o[/tex]
Law of cosines: [tex]a^2=b^2+c^2-2bccosA[/tex]
[tex]a^2=(6)^2+(4)^2-2(6)(4)cos55^o=36+16-2(6)(4)0.5735[/tex]
(cos[tex]55^o[/tex]=0.5735)
[tex]a^2=24.472,a=4.94\approx 5[/tex]
The length of the diagonal 'a' is 5.
