SOLUTION: If 7f-6f= 13 what does f equal?

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Question 1125918: If 7f-6f= 13 what does f equal?
Found 3 solutions by Edwin McCravy, jim_thompson5910, MathLover1:
Answer by Edwin McCravy(20060)   (Show Source):
You can put this solution on YOUR website!

7f-6f = 13, since 7-6 = 1, then 7f-6f = 1f 1f = 13, since 1f = f, so f = 13 Edwin

Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website!

Think of f as an actual object, say it's a flute. If we have 1 flute, then we can simply write f or 1f. Having 2 flutes means 2f. Three flutes would be written in shorthand as 3f. And so on.

For our equation,
7f = 7 flutes
6f = 6 flutes

Writing the expression 7f-6f means "we had 7 flutes, and then we took away 6 flutes". So that means we end up with 1 flute or 1f or just f. This property is called "combining like terms". Like terms have the same variable to allow for such combination.

Therefore, 7f-6f = 13 turns into 1f = 13 or f = 13

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Let's check the answer.

Replace every copy of 'f' with 13 and use PEMDAS to simplify the left side

7f-6f = 13
7*13-6*13 = 13 .... every f replaced with 13
91 - 78 = 13
13 = 13
We end up with a true equation, so that confirms that f = 13 is the proper answer.

Answer by MathLover1(20850)   (Show Source):
You can put this solution on YOUR website!

..........recall the distributive property