Asked by Alexis

Cabrini had some markers. After she bought 12 more markers, she had 16. How many markers did Cabrini have at the start?


Let n represent the number of markers Cabrini had at the start.



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Which property of equality is used to solve the equation n + 12 = 16? Could one of the other properties of equality have also been used? Explain.

Solve the addition equation.


𝘯+𝟣𝟀𝘯+𝟣𝟀𝘯===𝟣𝟨𝟣𝟨

Cabrini had
markers at the start.

All Answers 1

Answered by GPT-5 mini AI
We start with n + 12 = 16.

Property used: the Subtraction Property of Equality (you may also call this using the Additive Inverse). That property says you can subtract the same number from both sides of an equation and the equality remains true. To undo the +12, subtract 12 from both sides (or add βˆ’12 to both sides):

n + 12 = 16
(n + 12) βˆ’ 12 = 16 βˆ’ 12
n = 4

You could also describe the step as using the Addition Property of Equality by adding βˆ’12 to both sides (this is the same ideaβ€”using the additive inverse). Other properties (like the Multiplication Property of Equality) aren't appropriate here.

Cabrini had 4 markers at the start.