Algebra Problem

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Algebra Problem

by phoenix9801 » Sun Jul 22, 2012 11:00 pm
Please explain how to solve this problem step by step instruction. I am week on Algebra, hence please simple in explanation. Thanks

1-
I am not sure how they got x = -18 in one step process or they solved it?

0 = x/2 + 9

x= - 18


2-
The Same here also.

0 = x /1,000 + 1,000,000

x = -1,000,000,000


3-
Same here as well, not sure how they got rid of the negative?

0 = z(-3) + 18

3z = 18

z = 6



4- Here is the same, not sure how they got rid of the zero and number 2. Then came up answer as 4/3=x???

0 = 3/2x -2

2 = 3/2x

4/3 = x
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by Birottam Dutta » Mon Jul 23, 2012 12:16 am
First of all get this general fact clear:

A+b=0=> a= -b (taking b to the other side of the equality sign ). And sign changes when you take any quantity to the other side of the equality sign.

Now question 1. 0= x/2 + 9. Drawing analogy form above, here a= x/2 and b=9.

So, taking b to the other side, x/2=-9 => x= (-9)*2 = -18.

Solve the second question in the exact same way.

For the third, z(-3) + 18 =0 or -3z+18 =0. Taking -3z to the other side, we get, 18=3z (sign changed to positive for -3z to +3z)

=> z= 18/3 = 6.

Solve 4 in this way as well. If any problems, I shall explain further :)