Question

Help please.. I'm stuck...(Algebra)
x-y=5
2x+y=6
-3x+y=-6
x-y=4

Answer 1

(All seperate problems.) I just need a demonstration or a lil help with the ones that look a liiittle bit different. so i can carry on by myself from there

Answer 2

so all are separate?? like not in pairs or anything?

Answer 3

Nope all seperate. Sorry didn't make that clear at first.

Answer 4

I just have to solve for x and y. It also says i can use 0 to find the value of each easier.

Answer 5

if it's all separate..then even I can't do. Well one cuz there different terms and normally for two or more different terms, the equation comes in pairs so you can use simultaneous equation

Answer 6

Dunno it says here. (The points where x=0 and y=0) because they are usually the easiest to find. Then here are the problems (seperate).

x-y=4 x-y=5 2x+y=6 so on..

Answer 7

is this an equation from a graph?

Answer 8

Yes, It tells me to graph afterwards.

Answer 9

ahhh

Answer 10

first I would rearrange it so equation starts off with y=
imma use the second one as an example

Answer 11

so 2x+y=6
y=6-2x

Answer 12

For example 2x+y=6 I subtract 2x from both sides and get...

y= -2x + 6

I guess having the idea of 2 variables gets me..

Answer 13

as in it confuses you?

Answer 14

Just the general idea of having 2 variables gets to me. That's one of my weaknesses.

Answer 15

ahh ok ok well if its a graph its not as bad xD

Answer 16

so the equation is y=6-2x
so to find the y-intercept you substitute x with 0 so:
y=6-2(0)
y=6
next you find the x-intercept by substituting y with 0 so
0=6x-2
2=6x
2/6=x
so you plot the co-ordinates (.3,6) on you graph

Answer 17

that could be what I call a starting point
then you can repeat the process using another easy number say "5" and then plot the point on the graph. Then you draw a straight line connecting the two dots and you're done

Answer 18

okay, and to make it more clear on my graph, can i for example add a 1 under any whole number to make it a fraction and use that rise over run method? would it still work?

Answer 19

are you trying to find out the gradient?

Answer 20

(also on which may i use it if it does work, because if i use it on one it may give a completely different point resulting it NOT to be a straight line.

Answer 21

Nah but, just wanna see if it works because, with 3 points it looks better :P

Answer 22

and i also get a better understanding of the rise over run thing.. lol

Answer 23

haha if it's possible could you draw it as im not really understanding what you're saying. sorry >.<''

Answer 24

like what number are you add ing a 1 underneath it?

Answer 25

Any number like this...

we got (3,6) right? So add a number underneath any 1 of those to make it a whole number. Then we do the rise/run method. I want to see if it still works and so i can plot another point in that line that connects with x=3 y=6

Do i explain myself a little better?

Answer 26

ahh it was 2/6=.333...

Answer 27

now im confused as to where you got those numbers xD..

Answer 28

LOL ok!
i got the 6 from subsituting x with 0

Answer 29

Yup yup but the 2? o.o

Answer 30

and the 2/6 or .33 from substituting y with 0

Answer 31

those two numbers give the coordinates of the graph right

Answer 32

wasn't it a 3 though o-o

Answer 33

no there was a .

Answer 34

if you divide 2 to 6 you get .33333 but i just shortened it to .3
maybe you didnt see the dot?

Answer 35

2 by 6*

Answer 36

i did, just lost myself lol

Answer 37

you got 0.333?

Answer 38

yep, but i think this leads to some other formula and or method to a different thing.. lol..

like for example i wanna see if i do the \[rise \over run\] thing for example on the graph it's.. (1,3) . that dot connects with the line we get from 2,6

Answer 39

i see. you can do the rise over the run thing by looking at the number next to x. since it is a 2 you move right 1 unit and up 2 units

Answer 40

you can only do this if you already have a point and that's where the substituting the x and y with 0 comes in. The two numbers give you the coordinates and that's where you can start doing the rise over run thing

Answer 41

Ooh okay then, i think i understand this now. :D thanks

Answer 42

sorry since it toook reaaaaaaaaaallly long >.<''

Answer 43

nah it's okay, i always forget to do the simplest steps lol xD

Answer 44

lol if you need any help with the others feel free to ask =]

Answer 45

i think i just miight.. lol

Answer 46

In here in this problem:

x-y=5
I get to the part where it's
-y=-x+5

But then I need to substitute, or do I multiply EVERYTHING by -1 to make the variables positive?
I remember getting confused on this cause my teacher taught me to put in this form:
-y=-(0)+5

Answer 47

its better to not confuse yourself so multiply everything by -1

Answer 48

so you should get y=x-5