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Can't remember how this equation goes... f(-7) = x - 10. Is it 10 - x = f(-7) or x - 10 = f(-7)?

Tried looking it up, and can't find it in math book.

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It'd be f(-7)=(-7)-10. This is algebra right? what gradde?

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Pre-Alg, actually. 9th grade. I didn't want to go for the harder class of regular algebra. I could do it, but I'm known to not turn stuff in.
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oh I'm in 8th doing pre-alg. its pretty easy. hope this helped ya(;(;
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I dunno. I can't turn the work in anymoreor last quarter, but I still want to know how it works, been a while since I did this type of math... like... 4 years? Anyways, thanks ;)
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wow. Long time. and welcome(:
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x - 10 = f(-7). ANSWER
If you solve it it would be
-7 - 10 = -17
(please comment if you have a question)

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Well the question is to find out what x is, it gives what y is (f[-7]). Only one that could make sense would be the choice -3 f(-7) = -3 - 10 (if it works right to left, but not sure if it works that way, or left to right like it normally does).
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f(-7) = x - 10 means "put in -7 for x
and work out the problem."
So f(-7) = -7 - 10 = -17.
You don't find out what x is. It has already told you that x = -7.
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You could state the problem this way:
Find y if y = x - 10 and x = -7.
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Does that help?
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Here's the question: Given f(x) = x 10. What is f(7)? So I automaticlly think that f(x) is f(-7) because of the wa it is written. Am I just reading it wrong?
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f(-7) is different than f(7).
Examples:
Given f(x) = 2x + 1, what is
1) f(7) ?
f(7) = 2(7) + 1 = 14 + 1 = 15
2) f(-7) ?
f(-7) = 2(-7) + 1 = -14 + 1 = -13
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Does that help?
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I don't think I'm going to get it. It jumbles up real quick for me... Oh well, thanks for trying.
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With math, lots of times, if you leave it alone for a while, you'll understand it later. Try that.
Also I think I didn't understand your question very well and was not doing a good job of answering it.
You can always ask more questions in the future. Don't give up!
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