Hello Web2.0Calc community,
I know that distribution is one of the easiest things in math, but somehow this one problem my sister is having is frustrating my whole family as we're trying to figure it out. It is:
Solve for x.
- ( x - 3 ) - 4 ( x - 1 ) = 14
The textbook says that the answer is -7/5. I believe this is true because I tried it on my TI-89 Graphing Calculator, but it doesn't make sense to any of us.
I, personally, would distribute the negative in the front and the 4 (NO negative), getting this:
-x + 3 - 4x - 1 = 14
I would then combine like numbers and solve the problem... getting me a -10.
After thinking it over for a while, I tried something on my calculator, and apparently...
- ( x - 3 ) - 4 ( x - 1 ) = - ( x - 3 ) + (-4 ) ( x - 1 )
... because when you substitute -7/5 for x, both times you get 14.
How is this possible? Has there always been an invisible plus sign whenever you distribute? Please try it on your calculator too (or even this web calculator) and help us with this!
Thanks,
Alexis
+36923 - ( x - 3 ) - 4 ( x - 1 ) = 14
= -x+3 -4x + 4 = 14
= - 5x + 7 = 14
= -5x = 7
x = - 7/5
+259 Eps answer is right, but if you didnt catched it you made a mistake in ur 2nd calculation.
-4(x-1) is equal to -4x+1 and not -4x-1
I read ur answer again. Well im sorry if i missunderstood you as my english aint the best, but normally u dont write a plus in front of numbers. The same doesnt count for the - thought.
-4x(+x-1)+-4(+x-1) is the same.
Every number or variable has a plus or minus assigned to it, thought you dont write the plus out all the time.
What you did was calculating the following:
-4x(+x-1)-(+4(+x-1))
U switched the plus and minus, and bracket out the 4.
