is -x-4x=3x??

Question

is -x-4x=3x??

anonymous · Answer

only if x=0

mathstudent55 · Answer

-x is the same as -1x
-4x is -4 x
If you had -1 -4 what do you get?

mathstudent55 · Answer

-1 - 4 = ?

anonymous · Answer

-5?

anonymous · Answer

im having a lot of trouble with this Solve the system.
y = 2 - x and y = 4x + 7
 
    (1, 1) 
   (1, 3) 
   (-1, 3) 
   (-1, 1) 
   no solution 
 
im prettyy sure tis no solution

mathstudent55 · Answer

Right, so since -1 - 4 = -5, then -x - 4x = -5x

mathstudent55 · Answer

Now the system. Again, you have the two equations solved for y already, so use substitution.

mathstudent55 · Answer

Do you remember from the two previous systems what to do next?

anonymous · Answer

yes im working ion it

mathstudent55 · Answer

Ok, let me see what you're up to since you're having trouble with it.

anonymous · Answer

ok so i had 2-x=4x+7
                 2-x +2=4x+7+2
                  -x=4x+9
                    -x-4x=9
                      now im stuck

mathstudent55 · Answer

The 2 on the left side is positive, so you need to subtract 2 from both sides.

anonymous · Answer

-x (so -1x) take away 4  more x's. 
It's like being $1 in the hole in the bank account.
Spend four more bucks, and you are $5 in the whole, not $3.

However...
-x - 4x = 3x is interesting because:
-x - 4x + x = 3x + x
Then we have -4x = 3x
Then as said above, if x = 0, then it is true, otherwise no.

Hope this helps.

mathstudent55 · Answer

2 - x = 4x + 7
2 - 2 - x = 4x + 7 - 2
-x = 4x + 5
Now subtract 4x from both sides

anonymous · Answer

-4-4x=5

mathstudent55 · Answer

-x - 4x = 4x - 4x + 5
-5x = 5

anonymous · Answer

x=-1?

mathstudent55 · Answer

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