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MathNub
Sep6-11, 12:03 PM
How do I find the meaning of x in: 0,3x-6-x=-4,6 ? ;/

eumyang
Sep6-11, 12:07 PM
Do you know how to solve linear equations?

MathNub
Sep6-11, 12:08 PM
0,3x-6-x=-4,6|+6
0,3x-x=1,4
-0,3x=1,4|:0,3
x=4,(6)

And I am lost now ;/ That number isn't right

eumyang
Sep6-11, 12:47 PM
0,3x-6-x=-4,6|+6
0,3x-x=1,4
-0,3x=1,4|:0,3
This isn't right. 0,3x - x does not equal -0,3x. It may be easier to think of it as;
0,3x - 1x
(a variable without a coefficient really means that the coefficient is 1)
So what does this equal to?

MathNub
Sep6-11, 01:44 PM
-0,7x=1,4|:0,7
x=2

0,3*2-6-2=0,6-8=-7,4

But then we get the wrong answer.

eumyang
Sep6-11, 04:39 PM
-0,7x=1,4|:0,7
x=2
No... :cry: the bold should be -0.7, not 0.7.

0,3*2-6-2=0,6-8=-7,4

No... :cry: :cry: you need to follow the order of operations! Ignoring that we have the wrong answer for the moment, the multiplication comes first, then the 1st subtraction, and then the 2nd subtraction. You multiplied, and then did -6-2, which is wrong.