simplify d(-2d + 4) + 15d (explain the steps, please!)

collier

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Aug 29, 2006
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Can someone help me out. I need to know how to figure out a bunch of problems but ill give some. Can you explain step by step what to do?

Simplify
d( -2d + 4) + 15d
 

tkhunny

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The idea is to use properties you have been given to simplify the expression.

Some properties might be:

Associative for Addition or Multiplication
Commutative for Addition or Multiplication
Distributive Property of Multiplication over Addition

Are these ringing any bells?

d( -2d + 4) + 15d

Distributive Property of Multiplication over Addition

-2d^2 + 4d + 15d

Associative for Addition

-2d^2 + (4d + 15d)

-2d^2 + 19d
 

collier

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Aug 29, 2006
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Well you see I never took pre-algebra and I got put into Algebra 1 which I dont know anything about, and I told my teacher and she said that all classes are full for algebra 1 so I have to stay in that class and I know nothing at all!! and theres a test on fridaY~
 

tkhunny

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You had better look up all these properties and get used to them and how to use them. Ask you teacher to show you where they may be listed all together.
 

collier

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Aug 29, 2006
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tkhunny said:
Some properties might be:

Associative for Addition or Multiplication
Commutative for Addition or Multiplication
Distributive Property of Multiplication over Addition

Are these ringing any bells?

d( -2d + 4) + 15d

Distributive Property of Multiplication over Addition

-2d^2 + 4d + 15d

Associative for Addition

-2d^2 + (4d + 15d)

-2d^2 + 19d
Which means?
 

stapel

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collier said:
Which means?
The tutor explained the entire process, both by naming the rules you need to use, and by showing all of the steps. It would be hard to make the explanation much more clear, and yet it seems to be making no sense to you, nor sounding at all familiar to you. This bespeaks a serious lack of background material.

You might want to consider having a serious talk with your academic counsellor regarding course placement, so that you can get the necessary foundational material. Once you have that, the step-by-step solution you have received will make perfect sense.

Good luck!

Eliz.
 
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