Question

Using elimination, what are the values of x and y for the system of equations below?
2x+y=10
4x-y=8

Answer 1

what are the steps to take in order to eliminate?

Answer 2

im sorry i was hoping you would know. the possible answers are
A.x=-9, y=28
B.x=-1, y=12
C.x=3,y=4
D.x=6,y=8

Answer 3

i DO know ... but im not the one that needs to learn it :) i can hlep you out if you are stuck

Answer 4

the elimination method is named that becasue we get rid of one of the variables ...

Answer 5

and that can be done by adding the equations togther; but first we might need to modify one of them by multiplication

Answer 6

if we add these equations togther; will one of the variable go away?

2x+y=10
4x-y=8

Answer 7

the Y (i think)

Answer 8

very good :)

so lets add them and see ..

2x +y = 10
4x -y = 8
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6x +0 = 18 ; you wwere right :) now how does this make our life easier?

Answer 9

do you subtract 18 from both sides or substitute something?

Answer 10

not quite. its possible, but it doesnt get us anywhere.

6x = 18 ; this means that 6 times "something" equals 18

what does x have to equal ??

Answer 11

3

Answer 12

excellent; now we can stop there and check the answer opitions to narrow it down ...

Answer 13

which answer has x=3 in it?

Answer 14

haha its pretty obvious, C right

Answer 15

yes :)

but to dbl chk; lets see if y=4 will work out for us ...

2(3) +4 = 10
6 + 4 = 10 ... thats good


4(3) -4 = 8
12 -4 = 8 ; and its works for that one too ... id go with C :)

Answer 16

Thank you! oh and im brand new to this site. How do i give you props? do i click the good answer thing?

Answer 17

if you feel that you have been given a good answer, the good answer button is there for you to express it :)

and a simple thank you goes along way too

Answer 18

if you dont see a good answer button; you can refresh your browser by hitting the f5 key. :)

Answer 19

ok good i did both

Answer 20

thanks again

Answer 21

youre quite welcome, good luck ;)