You can
put this solution on YOUR website!There are four simple rules to follow in solving this problem. These rules are:
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(1) Replace f(x) with y
(2) Swap x and y
(3) Solve the result for y
(4) Replace y with the notation
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You are given the problem
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Let's apply the rules one at a time.
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Rule (1) Replace f(x) with y. Do this and you get:
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Rule (2) Swap x and y. So in the equation for Rule (1) wherever you see a y, change it
to x and wherever you see an x change it to y. When you do that you get:
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Rule (3) Solve the Rule (2) equation for y as follows:
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Start with the Rule (2) equation:
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Let's first switch the sides of the equation just for convenience. Make the right side
go to the left side and the left side go to the right side. If you didn't switch sides,
it would still work out OK. All this switch involves is:
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Next make the -4 go away from the left side by adding +4 to it. But when you add +4 to
one side of the equation, you must also add +4 to the other side. The result of this addition
is that the equation is changed to:
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One last step. You are to solve for y, so you need to divide both sides by the multiplier of
y. In this case divide both sides by 5 to get:
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OK, we've done Step (3). Step (4) says to replace y with the notation
. That means
that the left side of the final equation in Step (3) is replaced and you now have:
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That's the answer! You are done! Easier than baking a cake, faster too, and a lot less
heat (maybe just as messy though).
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Just remember and practice the 4-step method and you'll be able to do lots of these
problems. Now go gettum ...
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