Exercise 3 Page 44

To solve for n, we need to isolate it by multiplying both sides of the equation by - 5. We should multiply because division and multiplication are inverse operations. We are allowed to do this by the Multiplication Property of Equality.

-n/5=-2

MoveNegFracToDenom

Put minus sign in denominator

n/- 5=- 2

MultEqn

LHS * (- 5)=RHS* (- 5)

n/- 5*- 5=-2*- 5

FracMultDenomToNumber

a/- 5* - 5 = a

n=-2*- 5

Multiply

Multiply

n=10

We will check our solution by substituting this result back into the original equation and simplifying. If doing so results in an identity, our solution is correct.

-n/5=-2

Substitute

n= 10

-10/5? =-2

CalcQuot

Calculate quotient

-2=-2 ✓

An identity occurs when the left-hand side and the right-hand side of an equation are equal to one another. Since substituting n=10 resulted in an identity, our solution is correct.