6класс решить (x-5/-7/4)/(x+5/+7/3)=-3/4

(х-5/3)-(х-7/4)/(х+5/6)-(х+7/3)=-3/4; ((3х-5)/3)-((4х-7)/4)/((6х+5)/6)-((3х+7)/3)=-3/4; ((3х-5)/3)-(6×(4х-7))/(4×(6х+5))-((3х+7)/3)=-3/4; (3х-5-3х-7)/3-((12х-21)/(12х+10))=-3/4; -4-(12х+4)/(12х-10)=-0,75; (12х+4)/(12х-10)=-4+0,75; (12х+4)/(12х-10)=-3,25; 12х+4=-39х+32,5; 51х=28,5; х=57/102; х=19/34