Big Ideas Math: Modeling Real Life, Grade 6
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Big Ideas Math: Modeling Real Life, Grade 6 View details
3. Solving Equations Using Multiplication or Division
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Exercise 7 Page 261

Use the Multiplicative Inverse Property to isolate y.

y=9

Practice makes perfect
To solve the equation, we have to isolate y on one side. Using the Multiplication Property of Equality, we will multiply both sides of the equation by 32. Then, we will use the Multiplicative Inverse Property.
6=2y/3
3/2* 6=3/2* 2y/3
â–Ľ
Simplify right-hand side
3/2* 6=3/2* 2/3* y
3/2* 6=1* y
3* 6/2=1* y
18/2=y
9=y
y=9
To check that this solution is correct, let's substitute y=9 into the original equation and simplify.
6=2y/3
6? =2( 9)/3
6? =18/3
6=6 âś“
Since the left-hand side and right-hand side are equal, y=9 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.