SOLUTION: What's 4a^2^ - a^3^ divided by a^4^ ? I have 36 +27 divided by 81 please can someone explain. a=-3

Question 1126432: What's 4a^2^ - a^3^ divided by a^4^ ? I have 36 +27 divided by 81 please can someone explain. a=-3
Found 3 solutions by Edwin McCravy, Theo, Alan3354:
Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!

You just need to add the two numbers in the numerator and then reduce the fraction: Edwin

Answer by Theo(13342)   (Show Source): You can put this solution on YOUR website!
looks like you have the right answer.

when you replace a with -3, the expression becomes (4*(-3)^2 - (-3)^3) / (-3)^4.

this results in 36 + 27) / 81 which results in 63/81 which results in 7/9.

to simplify the algebraic expression, your would do the following:

start with (4a^2 - a^3) / a^4.

factor out an a^2 to get (a^2 * (4 - a)) / a^4.

since a^2 / a^4 equals a^(2-4) = a^(-1) which is equal to 1/a^2, the expression becomes (4 - a) / a^2.

i'm not quite sure, but i think that's as simple as it gets.

when a = -3, that becomes (4 - (-3)) / (-3)^2 which becomes 7/9.

the original expression and the final expression give you the same answer, so it appears that the simplification is correct.

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
What's 4a^2^ - a^3^ divided by a^4^ ?
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4 a squared is 4a^2, not 4a^2^

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