Direct- and inverse-proportion functions

Represent and compare direct and inverse proportion using tables, formulas, and graphs.

Meaning

Direct proportion is written and inverse proportion usually with In the former, is constant for ; in the latter, is constant throughout its domain.

Example

For doubling from 2 to 4 doubles from 6 to 12. For instead halves from 6 to 3.Inverse proportion excludes One quantity decreasing as another increases is not enough to establish inverse proportion.

Practice for this concept

Scope and references

Topics

relationships among tables, formulas, and graphs

Learning goal

Represent and compare direct and inverse proportion using tables, formulas, and graphs.

Helpful background

Check constant ratios or products of two quantities.

Direct and inverse proportional functions

These ordinary choice questions provide limited practice in this concept. They do not establish independent solution, full-concept performance, or mastery.

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