Q varies inversely with x. If Q=12 when x=5, find the value of Q when x = 12.

Q = 5

Step-by-step explanation:

Given Q varies inversely with x then the equation relating them is

Q = ← k is the constant of variation

To find k use the condition Q = 12 when x = 5 , thus

12 = ( multiply both sides by 5 )

60 = k

Q = ← equation of variation

When x = 12 , then

Q = = 5

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below: