The table below shows how many words Maria can text in a given amount of time. The total number of words that Maria can text, y, is proportional to the time it takes her to type, x, in minutes. Which of the following equations represents the relationship between x and y? A. y = 1/40x
B. y = 80x
C. y = x + 80
D. y = 40x

 y = 40x

Step-by-step explanation:

the answer is y = 40x  

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.