Question

4(2x-1)-3=9(x-4) help?

Answer 1

POINTS:
1.An equation implies both sides of the "equal to" sign are the same.
2.X is an unknown quantity(A quantity =number(representative of some physical quantity)).
3.A simple bracket means that you need to multiply the terms(all of them) by the number outside the bracket.

Answer 2

where exactly are you stuck ?

Answer 3

ok @lina17.. what do u get after multiplying 4 inside...

Answer 4

(8x-4)-3=9(x-4)

Answer 5

that is right

Answer 6

simplification: This means you are trying to simplify your problem by reducing the number of terms.You can do so by adding like terms,multiplying inside the bracket,etc....ON BOTH SIDES OF THE EQUATION.....

Answer 7

so i multiply 9(x-4)

Answer 8

yes

Answer 9

so it would be (8x-4)-3=9x-36

Answer 10

that is correct.good job! now if you have nothing to do with the terms inside a couple of brackets,then it is ok to remove them...

Answer 11

so do i subtract 8x-4

Answer 12

8x and 4 are subtractable once you know what x is.... but right now you cant subtract them...there is no way to do so......however ,look at the -4 and the -3 ...they are both similar,as in they are subtractable(that is why they are like terms).

Answer 13

oh okay

Answer 14

so it would be 8x-1=9x-36

Answer 15

remember you are subtracting 3 from negative four not positive four......

Answer 16

so its 8x--1=9x-36

Answer 17

lets go over this: (-4) - (3) = (-4) + (-3) =?

Answer 18

-7 ?

Answer 19

kudos!

Answer 20

so what will be the answer?

Answer 21

so its 8x-7=9x-36

Answer 22

yup

Answer 23

do i subtract 9x-36

Answer 24

try and think of what you will get if you were able to subtract them....is it possible to?

Answer 25

no

Answer 26

this is the part im stuck on

Answer 27

good... so bring the terms which you can add/sub/mul/div together.....

Answer 28

forget about the equal to sign for a minute ........just draw columns and write "like terms" in one column.........for eg: 8x and 9x are like terms put them in one column... similarly,tell me how many classifications/groups of terms are there?

Answer 29

2

Answer 30

?

Answer 31

you are right.......one is the constants and the other is the x terms

Answer 32

now focus on the equation and bring like terms together by moving them from one side of the equation to the other

Answer 33

so do i multiply ???

Answer 34

what do you intend to multiply?

Answer 35

8x and 9x

Answer 36

or no ??

Answer 37

no

Answer 38

so what do i do

Answer 39

imagine a situation where you have four types of goods to sell

Answer 40

ok

Answer 41

so is the answer 29

Answer 42

???

Answer 43

you have four bags:
chocolates
flour
water
sugar
........now someone steals some chocolate.....so in your inventory you will subtract it..
FROM THE TOTAL NUMBER OF CHOCOLATES THAT YOU HAVE.....NOT FROM FLOUR......OR ANY OF THE OTHER BAGS.....that is what you mean when you say.....'you can perform arithmetic operations only on like terms'..because it would not make sense any other way.
And in case you are wondering why a constant can be multiplied to x terms inside of a bracket ....it just means.....you have multiplied the no. of goods you had...you can double or triple your bags of chocolates......that makes physical sense..right?

Answer 44

because i subtracted 8x-9x = 1x which is just x and then i subtracted -36-7 =29

Answer 45

??

Answer 46

that step is wrong

Answer 47

did you understand my analogy for why we can perform operations on like terms?

Answer 48

kind of

Answer 49

i suggest you review your number line,basic addition and subtraction with negative numbers etc....in this case,8x-9x,you are subtracting a bigger no from a smaller no.

Answer 50

subtract while you count on your fingers......8 =8. so till 8 you can bend a finger for each number.after 8 you have no fingers left to bend down...so you go to the other side of zero giving you -1

Answer 51

??

Answer 52

@lina17 ........now tell me ..8x-9x=?

Answer 53

hope you understood........