Exercise 45 Page 66

How can you undo division?

s=- 104

Practice makes perfect

To solve the equation, we will isolate the variable. To undo the division in the given equation, we will use the Multiplication Property of Equality to multiply both sides of the equation by - 8.

s/- 8=13

LHS * (- 8)=RHS* (- 8)

s/- 8(- 8)=13(- 8)

a/(- 8)* (- 8) = a

s=13(- 8)

s=- 104

We will check our solution by substituting this result back into the original equation and simplifying.

s/- 8=13

s= - 104

\dfrac{{\color{#0000FF}{\text{-}104}}}{\text{-} 8}\stackrel{?}=13

- a/- b=a/b

\dfrac{104}{8}\stackrel{?}=13

Calculate quotient

13=13 ✓

Substituting s=-104 resulted in a true statement, so our solution is correct.

Communicate Your Answer p.61

Monitoring Progress p.62-64

Exercises p.65-66

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