Question

What is the value of the x variable in the solution to the following system of equations?
2x + 3y = 1
3x - 4y = 10

2

-1

1

-2

Answer 1

which method do you prefer to solve system of equations ?

Answer 2

substitution ? or elimination ?

Answer 3

which one is easier?

Answer 4

in this case, both are equally easy.

Answer 5

lets do, elimination.
multiply equation 1 by 4
what u get ?

Answer 6

don't want to try to solve on your own ??

Answer 7

sorry one sec.

Answer 8

sure, i'll wait.

Answer 9

8x+12y=4?

Answer 10

yes,
now multiply equation 2 by 3
what u get ?

Answer 11

9x-12y=30

Answer 12

good.
now add the 2 new equation which you got.

Answer 13

do u realise that you have eliminated y by doing that ?

Answer 14

17x=34
do i divide the other side by 17?

Answer 15

yup.

Answer 16

and u directly get x=.. ?

Answer 17

thank you. and you get 2

Answer 18

What is the value of the y variable in the solution to the following system of equations?
5x + 4y = 1
4x + 3y = -1
do i do the same here?

Answer 19

here you eliminate x
1) multiply eq 1 by 4
2) multiply eq 2 by 5
3) subtract.

Answer 20

i am confues. i got -1 for the y variable and thats not one of the choices

Answer 21

20 x+16y = 4
right ?

Answer 22

20x+15y =-5
right ?

Answer 23

yes

Answer 24

subtracting.,
16y-15y = 4-(-5)
y=9

Answer 25

and you get 1y=-1

Answer 26

my choices are -7

7

9

-9

Answer 27

4-(-5) = 4+5 = 9

Answer 28

oh crap i forgot to add the two. i only subtracted

Answer 29

happens.... any more problems ?

Answer 30

and are you understanding what is going on ?

Answer 31

sure. here i have to use the substitution method.
4x + y = 11
x + 2y = 8

Answer 32

isolate x from second equation.
what u get ?

Answer 33

is it 2y=8-x

Answer 34

but with that , you isolated nothing......not x, nor y.

Answer 35

try to keep x on left side.

Answer 36

oh ok its x=8-2y

Answer 37

yes, now substitute that in 1st equation.

Answer 38

3

Answer 39

yes, y=3
good work :)

Answer 40

x=. ?

Answer 41

2

Answer 42

correct.

Answer 43

For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

-x + 2y = -6
3x + y = 8

Answer 44

since x is negative do i need to divide the other side by -1?

Answer 45

either divide bot side by -1
or i would recommend you to
1)add x on both sides
2)add 6 on both sides.

Answer 46

-x + 2y = -6
2y = -6+x
2y +6 = x.