Question

for systems of linear equations in two variables,
2x+y=4
x-3y=9
do i just graph and find where the lines meet?

Answer 1

2X+y=4
X-3y=9
first get rid of x or y on both equation

Answer 2

well what i did was turn it into slope intercept so now they are
y=4-2x and y=-3-x

Answer 3

no look it as if it was an addition or subtraction problem, im drawing a pic its hard to explain. give me a sec

Answer 4

okay but the instructions say to solve each stem . if the system has an infinite solution set, specify it. if the system has no soulution say so.

Answer 5

multiply everythin the first equation by 3

Answer 6

you should get 6X+3y=12

Answer 7

how do you know to do that instead of graphing?

Answer 8

this way you are solving for X and Y, so you know exactly where the two lines meet on a graph

Answer 9

okay let me solve it real fast and i will tell you with what i end up with

Answer 10

so far i have x=3 then i plug it into one of the original problems right?

Answer 11

yup!

Answer 12

okay my final answer turned out to be (3,-2) thank you so much!!

Answer 13

hold on give me a sec sorry,

Answer 14

actually y should be 14

Answer 15

X is 3/5

Answer 16

remember X is your slope so its ok to have a fraction
Y=mx+b

Answer 17

this is how i solved it
3(2x+y=4)
x- 3y=9
6x+3y=12
7x+21
x+3

Answer 18

multiply the top by a -3 that way y turns to -3y and you can cancel out the
other +3y in the second equation
so you are left with
-6x=-12
x = 9

Answer 19

well wouldnt it work if i multiplied the top by 3 in order to cancel out the y coefficiant?