Ajewelry store buys small boxes in which to wrap items that they sell. the diagram below shows one of the boxes. find the lateral area and the surface area of the box to the nearest whole number. use the large 14 x 7 cm rectangles on the top and bottom as the bases. 35 cm2; 364 cm2. 70 cm2; 364 cm2. 35 cm2; 266 cm2. 70 cm2; 266 cm2.

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.