Given f(x) = 12x + 6 - 18x, find x if f(x) = -60

student0928

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I'm old school and didn't learn algebra the way kids do it now. Can anyone help me with this?

Given f(x)=12x+6-18x

Find x if f(x)=-60

Trying to help my neice with Algebra..PLEASE HELP
I m clueless! Please help me understand!
 
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tkhunny

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I'm old school and didn't learn algebra the way kids do it now. Can anyone help me with this?

Given f(x)=12x+6-18x

Find x if f(x)=-60


I m clueless! Please help me understand!
For starters, we probably need a better description for f(x).

Anyway, if we want f(x) = 60, simply do the substitution.

60 = {full expression for f(x)}
 

Dr.Peterson

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I'm old school and didn't learn algebra the way kids do it now. Can anyone help me with this?

Given f(x)=12x+6-18x

Find x if f(x)=-60


I m clueless! Please help me understand!
Essentially, you are told that "f(x)" is a name for 12x+6-18x. (I'm assuming that this is copied correctly; it feels wrong because it can be simplified, but that is not really a problem.) So you are being told to solve the equation

12x+6-18x = -60

The rest should be what you learned in algebra! If you didn't learn function notation, you can read the section in her book introducing it, and you'll find that it's really nothing more than a notation for things you've seen before.
 

Jomo

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I'm old school and didn't learn algebra the way kids do it now. Can anyone help me with this?

Given f(x)=12x+6-18x

Find x if f(x)=-60


I m clueless! Please help me understand!
if f(x) equals to two things like, 12x+6-18x and -60, then you set these two equal to one another.
 
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