Answer:
One equation to set up is 5x+6 = 16
That equation solves to x = 2
You bought 2 binders
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Step-by-step explanation:
x = number of binders
5x = cost of all the binders only ($5 each)
2*3 = 6 = cost of all 3 notebooks only ($2 each)
5x+6 = total cost of the 3 notebooks and x binders
5x+6 = 16 is one possible equation to set up
Other equations are possible.
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Let's solve for x.
5x+6 = 16
5x = 16-6 ... subtracted 6 from both sides
5x = 10
x = 10/5 .... divided both sides by 5
x = 2
You bought 2 binders
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Check:
1 binder = $5
2 binders = 2*5 = $10
Add this onto the $6 spent on the notebooks to get 10+6 = 16 dollars total. The answer is confirmed.