Question

If cos x >0 ans sin x= -4/5, then tan x=?

Answer 1

sinx = -4/5 = b/c.

a^2 + b^2 = r^2
.a^2 + (-4)^2 = 5^2
a^2 = 5^2 - (-4)^2 = 9
a = +-3
a = 3(Cos>0).

tanx = b/a = -4/3.