Solve with one variable for both sides.
Sin 40° + sin 130° + sin 220° + sin 310° = ...
sin 130° = sin 50°;
sin 220° = - sin 40°;
sin 310° = - sin 50°
... = sin 40° + sin 50° - sin 40° - sin 50° = 0
Answer: 0.
Answer:
40
Step-by-step explanation:
let the unknown be y (x is used as times(multiplication) )
(y-17)x-6=-138
add /-6 to both sides
y-17x-6/-6=-138/-6
y-17=23
make y independent/add 17 to both sides
y-17+17=23+17
y=40
or in an easier way
-138/-6 =23
23+17=40
simply reversing the question to get the answer