每个面包的利润为:x-5卖出个蠢逗数为:160-20(x-7)y与x之间的关系带基卖式锋迅:y=(x-5)*[160-20(x-7)]化简得:y=-20x2+400x-1500
每个面包的利润为:x-5卖枯敬出个数为:160-20(含液x-7)y=[160-20(x-7)](x-5)=[160-20(x-7)](没老慎x-5)= -20x²+400x-1500 =-20(x-10)²+100×20-1500=-20(x-10)²+500∴x=10角时利润最大Y=500
不懂