SOLUTION: Let the operation � be defined for all positive integers a and b by the equation a � b = a + ab For what value of b does

Question 117750: Let the operation � be defined for all positive integers a and b by the equation
a � b = a + ab
For what value of b does 5 � b = 15?

Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Simply use the definition: Since 5 � b = 15, this means 5+5b=15 (just plug in a=5 into ). Now let's solve for b:

Start with the given equation

Subtract 5 from both sides

Combine like terms on the right side

Divide both sides by 5 to isolate b

Divide

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Answer:
So our answer is

So when b=2, 5 � b = 15 is true
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