Posted on 01/09/2012 9:45:26 PM PST by The SISU kid
I know there a a lot of FReepers smarter than I, so here goes...got this presented to me for help & I for the life of me am stumped
4 [4 - 5x] = 6x + 4
says answer is x= 10/7
can someone show how to solve?
Thanks in advance....
4 [4 - 5x] = 6x + 4
16-20x = 6x + 4
16 -4 = 20x + 6x
12 = 26x
12/26 = x
6/13 = x
I get x = 6/13.
Multiply-out the left side, add 20x to each side, subtract 4 from each side, divide-through by 26. x = 12/26, simplifying to 6/13.
4 [4 - 5x] = 6x + 4
Rearrange to get X on one side of the equation.
4*4 - 5*4*x = 6x + 4
6x - 5*4*x = 4 - 4*4
(6 - 5*4 ) x = 4 - 4*4
x = 4 - 4*4 / (6 - 5*4 )
x = 4 - 16 / ( 6 - 20 )
x = -12 / ( - 14 )
x = 12 /14
x = 2*2*3 / 2* 7
x = 2*3 / 7
z = 6 /7
That’s how I’d solve it.
That weren’t so hard now, were it?
Just a thought, but I am not getting that X answer, are you sure the info is correct?
I am mean years of college I have written down lots of problems transposing numbers.
Dear Math,
I am not your therapist. Please solve your own problems.
Sincerely, Dave
( Couldn`t resist..Cheers)
4(4-5x)=6x+4
1) Distribute the 4:
16-20x=6x+4
2) Now solve for x:
-26x=-12
x = 6/13
I think the answer might be incorrect.
4(4-5x)= 6x+4
16-20x=6x+4
16-4=6x+20x
12=26x
x=12/26=6/13
My bad. Sign error. Lets try that again.
4 [4 - 5x] = 6x + 4
Rearrange to get X on one side of the equation.
4*4 - 5*4*x = 6x + 4
-6x - 5*4*x = 4 - 4*4
(-6 - 5*4 ) x = 4 - 4*4
x = 4 - 4*4 / (-6 - 5*4 )
x = 4 - 16 / ( -6 - 20 )
x = -12 / ( - 26 )
x = 12 /26
x = 2*2*3 / 2* 13
x = 2*3 / 13
z = 6 /13
No I’m not... that was my problem as well...I’m dealing with a high school teacher who says she’s having difivulty explaining it to a student...(you get the idea)
My first response was that the answer was incorrect!
Thanks guys & gals, I knew you’ld come thru
6/13 or .4615384615 is correct
4 [4 - 5x] = 6x + 4
16 - 20x = 6x + 4
-6x + 16 -20x = 6x - 6x + 4
-6x -20x +16 -16 = 6x -6x + 4 - 16
-26x = -12
x = -12/-26 = 6/13
Checked with http://www.wolframalpha.com/bing/?i=4(4+-+5x)+%3d+6x+%2b+4
says answer is x= 10/7
You can get x = 10/7 if you left of a negative sign on the first 4.
-4 [4 - 5x] = 6x + 4
-16 + 20x = 6x + 4
14x = 20
x = 20/14
x = 10/7
3:16
Who says the answer is x=10/7 because wolframalpha states x= 6/13.
Your decimal answer is incorrect, as 6/13 doesn’t end after just 10 decimal places. :)
Don’t let a democrat solve it, it will end up costing you a trillion dollars to solve it.
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