Question

The quantities x and y are proportional. Find the constant of proportionality r in the equation y = rx

Answer 1

Answer:

r = 7

Step-by-step explanation:

To solve this, we can plug in a pair of x and y values and solve for r.

y = rx | Plug in a pair

42 = r*6 | Now divide both sides by 6

7 = r.

We can test this by plugging in r with a pair.

y = (7)x

77 = 7*11, 77 = 77, This equation is correct.

Answer 2

Answer:

The constant of proportionality r in the equation is:

                       r = 7

Step-by-step explanation:

We know that for the equation of the type:

                $y=rx$

The constant of proportionality is given by the equation:

 $r=\dfrac{y}{x}$

i.e. it is the ratio of the output to the input values.

Here we have a table of values as follows:

      x        y

      2       14

      6       42

      11      77

Hence, with the help of any one set of value we will get the value of r.

We take the set (2,14)

i.e.

$r=\dfrac{14}{2}\\\\r=7$