Question

If y varies inversely as x, and if y = 4 when x = 72, find the following:

a) The constant of variation b) The value of y when x = 9

Answer 1

Answer:

a) The constant of variation is 288

b) The value of y is 32  when x = 9

Step-by-step explanation:

Given : y varies inversely as x

            if y=4 and x =72, constant = k = ?

Solution :  

a ) given y varies inversely as x

i.e. y α 1/x

   y = k/x

  k = yx

      = 4 x 72

      = 288  

b) when x=9

we know y = k/x

                  = 288/9

                  = 32

Answer 2

Step-by-step explanation:

y= x

k

y=4whenx=72

4= 72k

k=4×72

k=288