Question

solve for x: 2/5 (x-2)=4x help please help!!!!!!

Answer 1

\[\frac{ 2 }{ 5 } (x-2)=4x\]

Answer 2

As a start, multiply 5 both sides of the equation

Answer 3

That gets rid of the fractions

Answer 4

how would it be set up ?

Answer 5

hello

Answer 6

I'm here, have you multiplied both sides by 5 ?

Answer 7

ya but what do i multiply 5 from

Answer 8

Good question
before answering that,let me ask you a question

Answer 9

Have you seen a balance used to measure weights before ?

Answer 10

yes

Answer 11

http://www.presentation-process.com/wp-content/uploads/design-balance-scale.jpg

Answer 12

that one

Answer 13

do you know how it works ?

Answer 14

kind of

Answer 15

how does it work ?

Answer 16

dont you put them on each side to see which weighs less or more

Answer 17

Yes, what happens if you put 1kg on both sides ?

Answer 18

i would be even

Answer 19

good, what happens if you put 5kg on both sides

Answer 20

it would still be even

Answer 21

Exactly! As you can see, adding the "same" weight to both sides of the balance won't change the balance. It keeps the balance remain even.

Answer 22

An equation is also like that balance.

Answer 23

If you multiply/add same thing to both sides, the equation will not change. It will remain same.

Answer 24

\[\frac{ 2 }{ 5 } (x-2)=4x\]

Answer 25

so what em i suppose to do

Answer 26

Since I don't like fractions, and since I am allowed to multiply/add same thing to both sides, I'd like to multiply 5 both sides.

Answer 27

\[\color{red}{5\times }\frac{ 2 }{ 5 } (x-2)= \color{red}{5\times}4x\]

Answer 28

Fine with that step ?

Answer 29

yes

Answer 30

Notice that 5 in the top and bottom eat eachother out

Answer 31

\[\color{red}{\cancel 5\times }\frac{ 2 }{\cancel 5 } (x-2)= \color{red}{5\times}4x\]

Answer 32

\[2(x-2)= \color{red}{5\times}4x\]

Answer 33

do you know how to simplify further ?

Answer 34

um i think so

Answer 35

let me try

Answer 36

Awesome, so what would be your next step ?

Answer 37

\[2(x-2)= 2x-4\]

Answer 38

Excellent! that is your left side

Answer 39

5x4x=20x

Answer 40

2x-4=20x

Answer 41

em i right

Answer 42

Perfect!

Answer 43

so what do i do from there'

Answer 44

Our goal is to solve x
so we need to try and isolate it

Answer 45

do we subtract 2x from both sides

Answer 46

Yes :
\[2x-4 \color{red}{-2x} = 20x \color{red}{-2x}\]

Answer 47

so it would be 2x=18x

Answer 48

Nope

Answer 49

right hand side is correct,
left hand side is wrong

try again

Answer 50

oh it would be 6x=18x

Answer 51

looks you're adding apples and oranges

Answer 52

remember, you can only add/subtract like terms

Answer 53

so x = 3

Answer 54

wrong

Answer 55

dang

Answer 56

\[2x-4 \color{red}{-2x} = 20x \color{red}{-2x}\]

I cannot add -4 and -2x because these are not "like terms"

Answer 57

I can only add 2x and -2x, which gives me 0

Answer 58

\[2x-4 \color{red}{-2x} = 20x \color{red}{-2x}\]

simplifies to

\[-4 = 18x\]

Answer 59

do i divide

Answer 60

Yes, divide 18 both sides so that x gets isolated

Answer 61

x=2

Answer 62

i mean 9

Answer 63

\[-4 = 18x\]

divide 18 both sides and get

\[-\dfrac{4}{18} = x\]

which is same as
\[-\dfrac{2}{9}=x\]

Answer 64

so \(x = -\dfrac{2}{9}\)

Answer 65

oh ok

Answer 66

can you help me on one more

Answer 67

I'll try... tag me