Question

I know how to solve simultaneous equation but i think for this question i dont know some rule.
X+2y=2
x-y=-2

Eliminate method
1st eq -2nd eq

3y=4
y=4/3

What i dont get is how come in solution they dont multiply 2nd eq by 2 when i do it i get right x value but wrong y value

Answer 1

just first multiply 2nd equation by 2 and then use elimination method

Answer 2

and first question also by 2
2x+4y=4
2x-2y=-4
-----------
+6y =8
y=8/6
y=4/3

Answer 3

I know but in solution they didnt do it what my question is
If the question is like
x-y=9
X+2y=8
Is solve different to
2x-y=7
3x+y=6

Answer 4

now just put y=4/3 into any one equation either in 1 or 2
and get the x
i put it in equation 1
2x+4y=4
2x+4(4/3) =4
6x +16 /3 =4
6x +16 =4 x 3
6x +16 =12
6x=12-16
6x=-4
x=-4/6
x=-2/3

Answer 5

2x-y =7 eq#1
3x+y =6 eq#2 since just use the addition method so ,it will be
-------
5x =13
x=13/5
and now put x into any equation and get the y

Answer 6

U know the initial step 2x+4=4 +2x-2y=-4
How come 4+(-4) became 8 do we neglect the sign

Answer 7

Srrry after long time i have started doing maths

Answer 8

in the elimination method sign of second terms change if u are using elimination method
if there is + ve sign then it will convert into -ve okay?

Answer 9

have u got it?

Answer 10

Thank u

Answer 11

not say thank u
Just help three persons and say to them help more three persons anywhere okay?

Answer 12

@Haseeb96 taking movie morals too seriously aye !

Answer 13

@ayeshaafzal221
just be +ve
I watch movies for both the things i.e. entertainment and also lesson

it is good lesson for us if we adopt it
but we are pakistani and t
how can we keep our mouth silence or irritate the other till our words didnt hurt the other one 's heart and mind. :P

Answer 14

I dont know what pakistan u talking about i aint like that k maybe a little bit but ur right we shuld adopt good things so i shall help three people!:D @Haseeb96

Answer 15

haha

oh ho
acting karna koi tm se sikhe :D

Answer 16

do u not know the pakistan ?

jis mulk ne tmhe rehne ki ijazat di aj os ka name lete hwe tmhe shamram ati hai
aur dosro ko bhata ne mein bhi

Answer 17

K i dont know that much of urdu @Haseeb96

Answer 18

okay where are u from?