Diketahui Cos a= -12/13, 180

cos a = x/r = -12/13
tan a = y/x
*cari y
y = akar( 13^2-(-12^2))
= akar (169 -144)
= akar 25
= 5

cosec = r / y
= -13/5 (negatif karna di kuadran 3)
tan a = y/x
= 5/12 di kuadran 3 nilai tan positif


good luck...