Question

|2x-4|-1=5

please show work.

Answer 1

oh i remember this ^^ i did it last week! ok so isolate the absolute value first so get rid of the -1 now what do you have?

Answer 2

Alright, you're going to want to isolate the absolute value first. So how would you do that?

Answer 3

2x-4=5?

Answer 4

yes you can also have 2x-4=-5 or did you learn that?

Answer 5

yes

Answer 6

tay, now just combine like terms and divide, what do you get?

Answer 7

Not quite, you're going to want to keep those absolute bars up.
So first, you're going to want to isolate it.

|2x-4|-1=5
Let's get the 1 away from the absolute value bars. You can do that by adding 1 to both sides.
What do you get?

Answer 8

oh yeah 1+5 is 6 so instead of the or fact i said it will be 2x-4=6 or 2x-4=-6

Answer 9

wait there is another person saying something different

Answer 10

im confused :(

Answer 11

sorry i wasn't looking at the problem she is right, add one to both sides then take away the bars

Answer 12

|2x-4|-1 + 1=5 + 1
|2x-4| = ?

Answer 13

The 1s on the left side cancel out, so you have:
|2x-4| = 5+1
Or
|2x-4|=6

Okay, so in order to get rid of the absolute value parts, you have to consider both the positive and negative case:
The first case is:
2x - 4 = 6

What's the second case?

Answer 14

... i don't know

Answer 15

honey.... just make the = s negative number..... does that make sense?

Answer 16

|2x-4|=6 could equal either
2x-4=6 (which is the same equation with the bars removed)
OR it could be:
2x-4 = -6 (this is the negative case)

So you have two equations you have to solve:
2x-4=6 AND 2x-4 = -6

Answer 17

I'm just helping my brother with his homework

Answer 18

and i can't explain it so he can understand

Answer 19

oh just explain it to him by telling him that you have to remember to subtract and divide..... it's really simple so idk what else to say

Answer 20

i am the brother and i still don't understand you guys

Answer 21

ok where are you getting confused hun?

Answer 22

so the problem is 2x-4-1=5 and everyone keeps saying you have to get rid of the 1?

Answer 23

Yes, because you want to isolate the absolute value (get it alone.)

Answer 24

ok then what

Answer 25

how

Answer 26

so you add the 1 to the 5

Answer 27

Yep.

Answer 28

So now you have:
|2x-4|=6

In order to get rid of the absolute value bars, you have to consider both the positive and negative case:
The positive case is:
2x - 4 = 6

What's the negative case?

Answer 29

ok next?

Answer 30

could you just show me step by step

Answer 31

Okay, so you have:
|2x-4|=6

It's an absolute value equation and in order to solve it, you have to drop the absolute value bars. In order to do that, you have to write two equations (and solve both.)

The first case is the easiest to figure out since all you do is drop the bars:
2x - 4 = 6

The second case is where you have to solve the negative case. Here you just make the 6 negative (if it were an inequality you'd have to switch the sign too.)

So the second case is:
2x - 4 = -6

So now you have two problems you have to solve:

2x - 4 = 6 AND 2x - 4 = -6

Answer 32

thank u i think i get it now