Substitution Algebra


Substitution Algebra

Product Sum

Cross Multiplication



kW kVA pf

Inductance in Series

Inductance in Parallel

Capacitance in Series

Capacitance in Parallel

Powers Roots


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Substitution Algebra

The formulas used by electricians to determine missing values for various quantities are like recipes. The technique of solution is to enter the known quantities in the formula where they go. Then perform the mathematical operations as needed. When the calculation is complete, the desired quantity is produced.

By strictly following the formula, and adhering to math procedures paying attention to order of operation, each result will be correct.

The difficulty encountered in substitution algebra may be in finding the correct formula which will allow the electrician to use given information to find desired information.

So the process of solving an algebra problem begins with extracting the given information from the set of facts.

Next, selecting a formula which uses what is given to find what is desired.

Substitution of the given values into the formulas is next. Lastly, the math is performed to produce the result.

So it is 





Many students of these calculations like to go directly from the formula to the calculator without entering the given information in the formula.

A tip toward more success with calculations is to take the time needed to enter the given information into the formula before reaching for the calculator.


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