∴ The daily sales volume is100-(x-10) *10.
∴y=[ 100-(x- 10)* 10]*x-[ 100-(x- 10)* 10]*8
=[ 100-(X- 10)* 10](X-8)
=- 10X^2+280X- 1600
=- 10(X- 14)^2+360
∴ The opening direction of parabola is downward, and the equation of symmetry axis is X= 14.
∴ when X= 14, y gets the maximum value of 360, that is, when the selling price is 14 yuan, it gets the maximum profit 360 yuan.
Answer: When the price is 14 yuan, the maximum profit is obtained, and the maximum profit is 360 yuan.