It is "directly".Originally Posted byAarxn

There are two proportions. Direct and Inverse.

Inverse is when two variables mutiply to a constant, thus,

thus, - they form a hyperbola.

Direct proprtion is when two variables divide to give a constant, thus,

thus, -they form a line.

The case here is,

where "l" is a constant, thus we have a direct proportion.

To learn more about direct and inverse proprtions.

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