Well...
Some information was cut off but I'll assume that its a parallelogram.
If it's a parallelogram, then angles 1 and 3 are equal and angle 2 and the angle marked as 110 degrees are equal.
Next we know that angles 1 and 2 are supplementary(adds to 180) so angle 1 is 70 degrees.
Because angle 3 is equal to angle 1, angle 3 is also 70 degrees.
Hope this helps :)
