Question

Find the constant of variation from the table given below:

x	3	5	7	9
y	12	20	28	36

Set up a table and solve the following problems. Use unitary method to verify the answer.

Answer 1

$$\begin{gathered} \mathrm{Since}\mathrm{it}\mathrm{is}\mathrm{a}\mathrm{direct}\mathrm{variation},\frac{x}{y}=k. \\ \mathrm{For}x=3\mathrm{and}y=12,\mathrm{we}\mathrm{have}: \\ k=\frac{3}{12}=\frac{1}{4} \\ \mathrm{Thus},\mathrm{in}\mathrm{all}\mathrm{cases},k=\frac{1}{4} \end{gathered}$$