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#1 2009-03-17 06:57:20

GeeGee
Member
Registered: 2008-09-27
Posts: 7

Help i have a test

Can you please tell me what this i about?

Here is one that the teacher put on the board:



7×[X+11 = X×10-10    ITU

  7x+77 = 10x-10        1-7x

     77 = 3x-10            1+10

      87 = 3x                1:3

       29 = x


and here are some of my other questions [ that we must do in the same way]


1)    15x + 3x - 6x = 96

2)    8z + 2 = 90

3)    7w ≤ 49

thank you, from

GeeGeedunno

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#2 2009-03-18 06:20:42

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: Help i have a test

1) Collect like terms;

12x = 96

Divide both sides by 12;

x = 96/12
x = 8

2) Subtract the two from both sides;

8z = 92

Divide both sides by 8;

z = 11.5

3) Divide 7 into 49 and you get 7, so;

w ≤ 7

So w is any value from negative infinity to 7

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