Question

Can I rewrite 2x=4+z as z=4-2x???

Answer 1

Nope... z = 2x - 4

Answer 2

no ,because

Answer 3

hmmm why is the 4 become negative if it is already after the = sign

Answer 4

*does

Answer 5

but the 4 is already after the = sign, why does the sign change?

Answer 6

only the z and 2x swap sides

Answer 7

the 4 is always left of the = sign though

Answer 8

not really

Answer 9

=4
-4= ?????

Answer 10

What grade are you, Chrissy?

Answer 11

year 8 uk school

Answer 12

yeah i know

Answer 13

how can the -4 still be negative even though its moved

Answer 14

that goes against everything I have learnt thus far

Answer 15

Alright but I think understanding these things by moving the variable is not much of intuitive and may cause confusion in new learners. So my attempt would be to proceed in the follow way:

You have \[2x=4+z\] and now you want to isolate z so you have to get rid of 4 from the right hand side .. we can do do this my subtracting 4 from the RHS but to preserve the equation you also need to subtract 4 from LHS so .

\[2x-4=4+z-4 \Rightarrow 2x-4=z\] Hence your answer.

Answer 16

@Hollywood_chrissy:Don't move things just read my answer and let me know if you didn't understand :)

Answer 17

I could kiss you @ foolformaths, @ diyadiya thank you for your patience with me.

Answer 18

Thanks,and glad to help .. you may try to kiss me but I think my gf is not gonna like it :P :D

Answer 19

I understand from linear equations that what you do to one side you must do to the other, so foolformaths you made perfect sense.

Answer 20

@Diya: Moving things gets more messy when dealing with inequalities

Answer 21

I am sure it is we all have a complex brain to program anything and everything ;) :D