Carolyn makes and sells necklaces. The material to make each neckalce costs $3.20. She has 12 necklaces to sell and wants to make a total profit of $54. The following equation describes the situation. 12 (x minus 3.20) = 54 Carolyn found that x = 7.7 and determined that she will make a profit of $7.70 on each necklace . Which error did Carolyn make? The solution means that she should charge $7.70 for each necklace. The solution means that each necklace costs $7.70 to make. The solution to the equation is not x = 7.7. Carolyn did not distribute the parentheses when solving.

A

Step-by-step explanation:

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.