Would someone PLEASE help!!!!! Math is killing ME!!!!!!!?

Question

I can't figure out how to do these math problems! could some one please EXPLAIN but not give the answer!
x -(3x-9)= -5 or
4x -(2x+3)=7

Answer 1

x-(3x-9)=-5
remove the brackets
x-3x+9=-5
simplify adding the like terms
-2x+9=-5
you want only the variable on the left hand side
so adding -9
-2x+9-9=-5-9
simplifying
-2x=-14
you want x
so divide bothsides by -2
-2x/-2=-14/-2
which gives
x=7

2.4x-(2x+3)=7
4x-2x-3=7
2x-3=7
adding 3
2x-3+3=7+3
2x=10
dividing by 2
x=5

Answer 2

Yeah, you have to be careful because of the negative in front of the paraentheses. Not sure what your teacher calls the procedure, but you need to distribute the negative to everything inside.

For example, the first problem, you literally have "x minues 3x MINUS negative 9 equals negative 5."

I guess you can think of it like this:

20-(10-8)

You have 20, but you're taking away 10-8...however, the the 10-8 is just 2, so you get 18. If you're working with variables, you have to do 20-10-(-8), which gets you 10 again.

Sorry...this is really hard to explain. Hopefully it made a little sense. Just try thinking about these problems that are all numbers...good luck. =)

20-(10+8)

10-(4-2)

10-(4+2)

Answer 3

Ok first you need to do the math
x-(3x-9)=-5 turns into
x-3x+9=-5 do the math again
-2x+9=-5 combine like term
-2x+9-9=-5-9 turns into
-2x=-14 then divide by -2 on each side to get the answer
x=7
the next one
4x-(2x+3)=7 multiply the number in quotes by the minus sign
4x-2x-3=7 combine like terms
2x=10 divide each side by 2
x=5

Answer 4

These 2 problems use the Distributive property. You need to distribute the negative to all the numbers inside the parentheses. Then, just combine like terms.

Answer 5

I am really bad at math myself :(

But I found this site for you:

http://www.math.com/