Question

how do you solve this system of linear equations?
x+y=240
18x+12y+3120

Answer 1

=3120*

Answer 2

deja vu

Answer 3

id assume the way youd solve it as you do any system of equations

Answer 4

but i dont know how to do any systems of equations...

Answer 5

you should get \[x = 40,\ \ y = 200\]

Answer 6

then i would advise you to go back and review the section that teaches you those methods before trying to learn how to actually apply those methods

Answer 7

You have 3 options to solving systems of linear equations (with 2 variables x and y):

graphing
substitution
elimination

Answer 8

but, i learned this in algebra 1, and now im in algebra 2 and forgot

Answer 9

thats a contradiction; if you learned it, then you would know it :)

Answer 10

there are many methods to solving systems of equations; some more labor intensive than others

Answer 11

the main objective to understand is that a solution means that when x and y have solid values; that they will produce the desired results

Answer 12

but it was in 7th grade now im in 9th and i need one of which i could show work.

Answer 13

these equation can be graphed by 2 lines; and where they cross is where the solution to the system is

Answer 14

so where they cross will be an ordered pair tho

Answer 15

yes, x = ? and y=? :)

Answer 16

x = 40 and y = 200

Answer 17

i would go after elimination; which is simply multiplying the top by -18 and adding the 2 together

Answer 18

ohhhhhhhhhhhhhhhhhhhhh.

Answer 19

x + y =240 ; *-18
18x+12y =3120

-18x -18y =240(-18)
18x +12y =3120
-------------------
-6y = 3120 - 240(-18)

y = (3120 - 240(-18))/-6

Answer 20

i get y = -1240 that way tho

Answer 21

http://www.wolframalpha.com/input/?i=solve+x%2By%3D240+and+18x%2B12y%3D3120

Answer 22

oh, i subtracted the right side instead of adding lol

Answer 23

y = (3120 + 240(-18))/-6 = 200 :)

Answer 24

thanks