Verified answer

as sin x = sin (180- x)

so if 180-x= 60 then x = 120 so 120 is the answer

60 X 180

for sine function, the value of x is always the same for 180-x since the function is symmetrical with respect to y-axis..

therefore sin(x)=sin(180-x)

if x=60 degrees, then

180-x=120 degrees..

which satisfies the condition 90 degrees<x<180 degrees

sin(60) = sin(180 - 60) = sin(120)

x = 120

120

remember the circle

120+60=180

so both of the sin's of these degree's are rad3/2