Question

Can someone tell me what I did wrong?
If possible, solve the system of equations. Use any method.

Answer 1

3x+5y=6 (1)
5x+7y=6 (2)


-5(3x+5y=6)
-15x-25y=-30

3(5x+7y=6)
15x+21y=30

-4y=0
y=0

Answer 2

3(5x+7y=6)
15x+21y=30

Answer 3

Theres something wrong with that.Keep in mind OPPOSITES CANCEL.

Answer 4

What? O.o

Answer 5

15+15= 30
we want to cancel the x value

Answer 6

-5(3x+5y=6)
-15x-25y=-30
same here
-15+-15=-30

Answer 7

-15x-25y=-30
15x+21y=30
4y=0

Answer 8

what did u do?

Answer 9

I have no clue what you doing. I am doing substitution method. The x is not suppose to just disappear like you have.

Answer 10

-5(3x+5y=6)<---wrong
-15x-25y=-30

5(3x+5y=6)
15+25y=30

15+25y=30
-15x-25y=-30

Answer 11

Get it?

Answer 12

the mistake is in the second eq:
\[3(5x+7y=6)\]
you get:
\[15x+21y=18\]
because 3*6=18, not 30 !!

Answer 13

They made a mistake on both.

Answer 14

There shouldnt even be 2 sets of equations

Answer 15

@Destinyyyy
15+25y=30
-15x-25y=-30
solve this

Answer 16

@Greg_D I see that now thank you.. Cannot believe I did that -.-

Answer 17

Im gonna let them finish up.

Answer 18

But there should not be 2 sets.

Answer 19

it was a system of 2 eqs from the begining of the problem...
the only mistake i can see is the one i pointed out earlier 3*6 is not 30

Answer 20

I have no clue what your talking about @pooja195

Answer 21

I know the final answer is (-3,3) ... But im not sure how they get -3

Answer 22

@pooja195 there are a lot of ways to solve the system, the one @Destinyyyy is using is fine, there was just that little mistake

Answer 23

once you get y=3, just replace that in any of the original equations...

Answer 24

Im only allowed to use elimination, graph, substitution.

Answer 25

Thank you @Greg_D

Answer 26

so you arent allow to use "any" method

Answer 27

-5 (3x+5y=6)
3(5x+7y=6 )

-15x-25y=-30
15x+21y=18

-4y=-12
divde both sides by -4
y=3

15x+21(3)=18

15x+63=18
subtract 63 both sides
15x=-45
divde both sides by 15
x=-3

Answer 28

Its any method of the three. I should of said that

Answer 29

notice how there is not 2 sets of equations in no way shape or for should u have 2 sets of equations even when doing elimination

Answer 30

Um the 3 is suppose to go into one of the original equation.

Answer 31

I know how to solve it. I just didnt see where I messed up. @Greg_D showed me my mistake.

Answer 32

look if:
\[y=3\]
and:
\[3x+5y=6\]
then:
\[3x+15=6\]
you can get x from there...

Answer 33

the same is done in the last part of @pooja195 last response :)