Rearranging Formulas II

Rearranging Formulas II

Slide: 1

Recall: Rearranging Formulas Recall: Given a formula with multiple variables, we can rearrange the formula for any variable.

Rearrange for t.

v = v0 + at

– v0 v t= a

We can also rearrange formulas involving algebraic fractions!

Slide: 2

Rearranging Formulas Involving Algebraic Fractions Step 1: Determine the Lowest Common Denominator (LCD) of the fractions.

Example

𝟏

𝟑

Rearrange the formula 𝒄 = 𝒂 + 𝟐𝒂𝒃 for b.

1 3 c= + a 2ab Slide: 3

LCD = 2ab

Rearranging Formulas Involving Algebraic Fractions Step 2: Multiply each term in the equation by the LCD.

Example

𝟏

𝟑

Rearrange the formula 𝒄 = 𝒂 + 𝟐𝒂𝒃 for b.

2abc = 2b + 3 Slide: 4

Rearranging Formulas Involving Algebraic Fractions Step 3: Isolate the desired term(s) using properties of addition and subtraction, and factor if necessary.

Example

𝟏

𝟑

Rearrange the formula 𝒄 = 𝒂 + 𝟐𝒂𝒃 for b.

2b(ac – 1) = 3 Factor out 2b Slide: 5

Rearranging Formulas Involving Algebraic Fractions Step 4: Isolate the desired variable using properties of multiplication and division.

Example

𝟏

𝟑

Rearrange the formula 𝒄 = 𝒂 + 𝟐𝒂𝒃 for b.

3 b= 2 (ac – 1) Slide: 6

Class Problems: Show the steps taken to rearrange the following formula.

𝟒𝒚 𝒙= 𝟏𝟐 − 𝒚

Slide: 7

𝟏𝟐𝒙 𝒚= 𝟒+𝒙

Class Problems: Show the steps taken to rearrange the following formula.

𝟏 𝟏 𝟏 = − 𝒑 𝒒 𝒓

Slide: 8

𝒑𝒒 𝒓= 𝒑−𝒒

Class Problems: Show the steps taken to rearrange the following formula.

𝟏 𝟐𝒄 − 𝟑 𝒄 + 𝟏 𝒂= + − 𝒃 𝒃𝒄 𝒄

Slide: 9

𝒃+𝟑 𝒄=− 𝒂𝒃 + 𝒃 − 𝟑