Question

324=1409-1400cos(x)
What’s x equal ?

Answer 1

x ≈ 39.2°

Explanation:

Given

324 = 1409 - 1400 cos x ( subtract 1409 from both sides )

-1085 = - 1400 cos x ( divide both sides by - 1400 )

0.775 = cos x, thus

x =
`cos^(-1)` (0.775) ≈ 39.2° ( to 1 dec. place )