[Ingtar]

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

[Black_Shark]

Who says the answer is x=10/7 because wolframalpha states x= 6/13.

[Yossarian]

Actually, Alpha just gave me the right answer of 6/13 .

That’s even using the link you provided right there.

[James C. Bennett]

I think Wolfram Alpha is using the input and wrongly utilizing them as two separate equations, and solving them simultaneously. Hint: the two lines on the graph.

I guess the software cannot take in an input in the format we humans are accustomed to.

[USNBandit]

the link you posted says the answer is 6/13

[cynwoody]

says answer is x= 10/7

Nope. Wolfram gets 6/13.

http://www.wolframalpha.com/input/?i=4[4-5x]+%3D+6x%2B4

[joe212]

re: Checked with http://www.wolframalpha.com/bing/?i=4(4+-+5x)+%3d+6x+%2b+4

Great link, thanks.

[ApplegateRanch]

Not now, it doesn’t; says 6/13

---

4 (4-5 x) = 6 x+4
Mathematica plaintext input:
4 (4 - 5 x) == 6 x + 4

Mathematica plaintext output:
{{x == 6/13}}