Question

tan (3x-30(degrees)) = -1, 0 14 years ago

Answer 1

if:
\[\tan(\theta) = -1\]
that means that:
\[\theta=135,315\]degrees. So now we have:
\[3x-30=135\iff 3x=165\iff x=55\]or\[3x-30=315\iff3x=345\iff x=115\]

Answer 2

oh, ohhhh, got it. thanks :D