2sin(45°+120°)=2(sin45°cos120°+sin120°cos45°)=2(sin45°cos(30°+90°)+sin(30°+90°)cos45)=2(-sin45°sin30°+cos30°cos45°)=
(8x - 3) - (3x + 4) = 5
8x - 3 - 3x - 4 = 5
5x - 7 = 5
5x = 5 + 7
5x = 12
x = 2,4