Question

I want to know is my answer right? some check it plz!
Solve using the substitution method.
1/2x-1/5y = 7,
1/6x+ 2/3= -4

my answer
Is this right? 1/2x-1/5y = 7, ---1) 1/6x+ 2/3= -4 ---2) Rearrange equation 2) 1/6x+ 2/3= -4 1/6x = -4 -2/3 x = -28 substitute x = -28 into 1) 1/2 x -28 -1/5y =7 -14 - 1/5y = 7 1/5y = -14 -7 y = 105

Answer 1

1/2x-1/5y = 7, ---1) 1/6x+ 2/3= -4 ---2) Rearrange equation 2) 1/6x+ 2/3= -4 1/6x = -4 -2/3 x = -28 substitute x = -28 into 1) 1/2 x -28 -1/5y =7 -14 - 1/5y = 7 1/5y = -14 -7 y = 105

Answer 2

is this right??

Answer 3

Wait...the second equation, doesn't have a y in it...Is that the way it's supposed to be?

Answer 4

1/2x-1/5y = 7,
1/6x+ 2/3= -4

Answer 5

like this

Answer 6

So, the second equation has no y in it, correct?

Answer 7

yes

Answer 8

\[\frac {x}{2}-\frac{y}{5}=7\] and \[\frac{x}{6}-\frac{2}{3}=-4\]

Answer 9

In the first equation multiply both sides by 10:

5x-2y = 70

In the second equation, multiply both sides by 6:

x+4 = -24

Answer 10

What you wrote:
-14 - 1/5y = 7 1/5y = -14 -7 y = 105
What I think would be correct:
-14 - 1/5y = 7
-1/5y=7-14
-1/5y=-7
multiply -5 to each side
y=35
Then you have to find x.

Answer 11

I messed that all up

Answer 12

im lost

Answer 13

(It was a little bit jumbled so it took me quite a while to follow what you did, but everything was fine until the end.)

Answer 14

Hahahha, um, do you get what I did?

Answer 15

no!

Answer 16

That's what I get

Answer 17

Wow...that's approximately 35

Answer 18

so maybe nitaleung's methods are accurate

Answer 19

LOL okay I'm confusing myself too. I should have added 14 instead of subtract...
-14 - 1/5y = 7
-1/5y=7+14
-1/5y=21
multiply -5 to each side
y=105
Oh pft, I'm such a doofus. --But I wonder how Hero got his answer then?? Donnice, you're straight on correct, ignore me please.

Answer 20

I'll recalculate....

Answer 21

y = 105

Answer 22

I did a wrong step somewhere the first time

Answer 23

:) great

Answer 24

so my answer right

Answer 25

U may always check this sort of thing by feeding your equations to the Wolfram god....

http://www.wolframalpha.com/input/?i=x%2F2+-+y%2F5+%3D+7%2C+x%2F6%2B+2%2F3%3D+-4