i need help with solving (4y-3)-(4-y)=3(y+3)

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santasad13

Junior Member
Joined
Jan 26, 2006
Messages
50
i cant figure out how to do this problem:

(4y-3)-(4-y)=3(y+3)

if i can just figure out how to do the next step, that would be enough for me to solve.
thanks
 
The problem may be that there is NO "next" step. You may do what you wish. Just pick something. It's kind of traditional to start at the left - but that's just a tradition.

(4y-3)-(4-y)=3(y+3)

Remove the first set of parentheses - They're easy.

4y-3-(4-y)=3(y+3)

The second set is a little trickier.

4y-3-4+y=3(y+3)

That required the Distributive Property. That's why you studied it.

Rearrange the left-hand side

-3-4 + 4y+y=3(y+3)

That required the Commutative Property. That's why you studied it.

Group things that are convenient.

(-3-4) + (4y+y)=3(y+3)

That required the Associative Property. That's why you studied it.

Simplify

-7 + 5y=3(y+3)

Now the parentheses on the right-hand side. Distributive Property again.

-7 + 5y=3y+9

It's much cleaner, isn't it? Add 7

5y=3y+16

Subtract 3y

2y=16

divide by 2

y=8

Great! But we're not done. Check your answer.

(4(8)-3)-(4-(8))=3((8)+3) -- ???
(32-3)-(-4)=3(11) -- ??
29+4=33 -- ?
33=33 -- Yes!!!! We have it.

One step at a time. Do not be so concerned about the order in which you do things. Do things correctly and the order of the things will take care of itself.
 
-(4-y) = -4+y

Ponder it until it soaks in. Use the explanation given above.
 
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