Big Ideas Math: Modeling Real Life, Grade 6
BI
Big Ideas Math: Modeling Real Life, Grade 6 View details
3. Solving Equations Using Multiplication or Division
Continue to next subchapter

Exercise 29 Page 263

Use the Division Property of Equality to eliminate the multiplication.

m=3/20

Practice makes perfect
To solve the equation, we have to isolate m on one side. Using the Division Property of Equality, we will divide both sides of the equation by 4. This will eliminate the multiplication and isolate m.
3/5=4m
3/5Ă· 4=4mĂ· 4
3/5Ă· 4/1=4mĂ· 4/1
3/5* 1/4=4m* 1/4
3/5* 1/4=m* 4* 1/4
3/5* 1/4=m* 4/1* 1/4
3* 1/5* 4=m* 4* 1/1* 4
3/20=m* 4/4
3/20=m*1
3/20=m
m=3/20
To check that this solution is correct, let's substitute m= 320 into the original equation and simplify.
3/5=4m
3/5? =4( 3/20)
3/5? =4* 3/20
3/5? =12/20
3/5? =12Ă· 4/20Ă· 4
3/5=3/5 âś“
Since the left-hand side and right-hand side are equal, m= 320 is the correct solution.

Extra

Properties of Equality

There are four main Properties of Equality that we use when solving linear equations.

Properties of Equality
Addition Property of Equality If a=b, then a+c=b+c.
Subtraction Property of Equality If a=b, then a-c=b-c.
Multiplication Property of Equality If a=b, then ac=bc.
Division Property of Equality If a=b and c is not 0, then a/c=b/c.

In later chapters, you will learn about some more advanced Properties of Equality. As an example, there is a property for when we need to eliminate a radical or an exponent.

Power Property of Equality

If a=b, then a^m=b^m.