To find x we are gonna use the cosine formula.
Cos 0 = adj/hyp
0 represents theta
Cos 0 = adj/hyp
Cos 0 = 25/40
Convert 25/40 to decimal from
25/40 = 0.625
On a scientific calculator press the key “2nd F” or “Shift” then “cos”(which would give cos inverse) then type 0.625 equal.
Cos-1 0 0.625
= 51.31 degrees
x is therefore 51.3 degrees to the nearest tenth