# Math Help - Brain Teaser

1. ## Brain Teaser

What is the value of 3-4/3x + 5 =7

-4 + 3=x +4

3-4= -x+6+11x+4x-3

-3 1/3x - 1/6= 1 1/3

2. Originally Posted by Megpup
What is the value of 3-4/3x + 5 =7

-4 + 3=x +4

3-4= -x+6+11x+4x-3

-3 1/3x - 1/6= 1 1/3
Can I be the first to say

What???

Are you trying to solve:
3 - 4/(3x + 5) =7

-4/(3x + 5) =4

-4 = 4(3x + 5)

-1 = 3x + 5

3x = -1 - 5 = -6

x = -2

-Dan

3. Originally Posted by Megpup
What is the value of 3-4/3x + 5 =7

-4 + 3=x +4
3-4= -x+6+11x+4x-3
-3 1/3x - 1/6= 1 1/3
Hi,

I assume that you want to solve
Code:
      4
3 - ---- + 5 = 7
3x
You'll get:
Code:
      4
8 - ---- = 7
3x
Subtract 8 on both sides:
Code:
   4
- ---- = -1
3x
Multiply by (-3x):

4 = 3x ==> x = 4/3. I really don't understand what you have done - honestly!

4. Originally Posted by earboth
4 = 3x ==> x = 4/3
Dont u mean x = 3/4 ??

Isnt it (3/4) * x ??

5. Originally Posted by janvdl
Dont u mean x = 3/4 ??

Isnt it (3/4) * x ??
No.

4 = 3x

4/3 = (3x)/3

4/3 = x

-Dan

6. If only people would use parenthesis...