If y varies inversely as x and y=3 when x=8 what is x when y=4

x = 6

Step-by-step explanation:

y varies inversely as x

y = k × 1/x. {where k is a constant}

when y = 3, x = 8

Therefore 3 = k/8 and k is 24

y = 24/x

When y = 4,

4 = 24/x

4x = 24

(dividing both sides by 4)

x = 6

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.