(X+86)×12-2×22÷8+{[(8+9)×40]-88}×6÷20%=17760
(X+86)X12-44÷8+{[17X40]-88}X6÷20/100=17760
12X+86X12-11/2+{680-88}X6÷1/5=17760
12X+1032-11/2+592X6X5=17760
12X+1032-11/2+592X30=17760
12X+1032-11/2+17760=17760
12X+(2064-11)/2=17760-17760
12X+2053/2=0
12X=-2053/2
X=-2053/2*12=-12336