Question

Solve system by elimination

6x+2y=20
8x+10y=12

Answer 1

lets eliminate the y variable by multiplying the first equation by 5
\[30x+10y=100\]
\[8x+10y=12\]

Answer 2

now lets subtract the first equation by the second

Answer 3

30x+10y=100
8x+10y=12 -

22x = 88
x =?

Answer 4

i subtract 88 by what..?

Answer 5

we are working our way down and subtracting...
30x+10y=100
8x+10y=12 -


30x-8x=22x + 10y-10y =0 (eliminated) = 100-12=88

Answer 6

therefore what is left after subtracting one equation from another is
22x=88
x=4

Answer 7

now sub in x=4 into any equation to find the y value

Answer 8

ah subtracting by one another

Answer 9

what is ur y value

Answer 10

it would be y= 16?

Answer 11

lets substitute x=4 into any of the two original equations.
6x+2y=20
6(4)+2y=20

now solve for y

Answer 12

alright

Answer 13

6 x 4 = 24 plus 2 =26?

Answer 14

24+2y=20
2y=20-24
2y=-4
y=-2

Answer 15

you subtract you don't keep adding oh wow

Answer 16

So both these equations
6x+2y=20
8x+10y=12

cross each other at (4, -2)

Answer 17

we substituted the x value we found from using the method of elimination

Answer 18

hmmm i can see how this might get confusing. happy to help if u have questions

Answer 19

so they must always cross, yes?

Answer 20

thanks a lot

Answer 21

i am not sure what u mean by cross. But the story is 6x+2y=20 and 8x+10y=12 are two straight lines and they cross each other at (4, -2). We can find out which points they both have in common by wither elimination or substitution.

with elimination we basicly got rid of one of the variables and solved to see what value we get. then substituted that value back into the original equation to find the other point... hope that makes sense.