x-(0.5x+5)-[0.5(0.5x+5)-10]-15=10先去中括号得 x-(0.5x+5)-0.5(0.5x+5)+10-15=10化简得 x-1.5(0.5x+5)=15去括号得 (1-1.5×0.5)x-1.5×5=15化简得 0.25x=22.5 x=90