Trig problem tan(2x)=-0.64976

Can anybody show me how to solve this?

first answer is wrong
that gives tan= + 0.64976.

you have to find the tan inverse of -0.64976, which gives in radians 0.5762, this is not the version you want, you want the pi - 0.5762 and 2pi - 0.5762 as those two angles have negative tangents.

so 2x= pi - 0.5762 and 2x= 2pi-0.5762

x= 1.28269 radians and x= 2.8535 radians

if you want it in degrees just multiply each angle by 180/2pi.

tan 2x = .64976
2 x = tan-1(.64976)
= 33
so x= 33/2 = 16.5 ans