What is the constant of proportionality "k"?

1 Answer
Nov 11, 2014

Direct Variation

If #y# is directly proportional to #x#, then we can write

#y=kx#,

where #k# is the constant of proportionality.

If you solve for #k#, we have

#k=y/x#,

which is the ratio of #y# to #x#.

Hence, the constant of proportionality is the ratio between two quantities that are directly proportional.


Inverse Variation

If #y# is inversely proportional to #x#, then we can write

#y=k/x#,

where #k# is the constant of proportionality.

If you solve for #k#, we have

#k=xy#,

which is the product of #x# and #y#.

Hence, the constant of proportionality is the product of quantities that are inversely proportional.


I hope that this was helpful.