solve: -4x = -28 please :)?

2009-10-30 9:42 am

回答 (17)

2009-10-30 9:51 am
✔ 最佳答案
Ok, so you have -4x = -28.

BUT!... WE WANT TO FIND THE VALUE OF x, not -4x

So lets get rid of number behind the x. How will we get rid of it? We must use the opposite sign, being either multiplication, division, addition or subtraction. How do we know which one to use? Think about it:

-4x is really -4 multiplied by x. So we'll use the opposite of multiplication - division. So we must now divide -4x by -4 (to get rid of the -4 and leave just: x=...) BUT WE'RE NOT DONE YET - you must still divide the other side by -4 as well. So we will also do -28 divided by -4.

Now you will have:

-4x = -28
/-4..../-4

x = 7 (remember when you divide a '-' by a '-' you get a '+')

We now have a form which is in: x=... Remember we only wanted to find how much just 1x is, not -4x.

Your answer is:
x= 7
2009-10-30 5:40 pm
4x = 28

x = 7
2009-10-30 5:24 pm
-4x = -28
x = -28/(-4)
x = 7
2009-10-30 5:14 pm
x=7
2009-10-30 4:54 pm
7
2009-10-30 4:50 pm
x=7
2009-10-30 4:48 pm
divide -4 on both sides like this -4x/-4= -28/-4
then do the math x= 7
i hope that helped :)
2009-10-30 4:47 pm
As b oth are minus figures remove the minus sign as they cancel each other out. (-2 x -2 = +4)

In your equation then

4x = 28
therefore x = 28/4

therefore x = 7
2009-10-30 4:46 pm
7

-28/-4 will give you x
2009-10-30 4:45 pm
7


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