Question

Solve the system of equations: y= x + 3 y= 2x + 4

Answer 1

there are two different methods you could use

Answer 2

the substitution method

Answer 3

ok

Answer 4

so up there you clearly wrote that y is equal to "x + 3" right?

Answer 5

yes

Answer 6

so couldnt we go to the other one and change y to "x+3"

Answer 7

oh ok yes we can

Answer 8

so
x+3 = 2x + 4
I just substituted "x+3" in for y =P

Answer 9

solve for x

Answer 10

so it would be -1 for x

Answer 11

I showed him the best method to use and he still didn't get it

Answer 12

yep so x= -1

Answer 13

i understand this method hero

Answer 14

now they usually also want y

Answer 15

yes so i will solve for y right now

Answer 16

would you plug in -1 for the y because for the method that our teacher taught us we plugged in the number that we got for x and used it in y

Answer 17

o no nevrmind

Answer 18

x= -1 no trickery =)

Answer 19

y = 4

Answer 20

y = x + 3

Answer 21

y = (-1) + 3

Answer 22

y =???

Answer 23

y=-1+3

Answer 24

2

Answer 25

ding ding ding

Answer 26

oh ok now im starting to understand it.

Answer 27

thats the goal!

Answer 28

yes thank you so much

Answer 29

what we have just done is found an x and found a y that satisfies both those equations

Answer 30

yes so that is easier than graphing in my opinion

Answer 31

yep way easier.. butt!! if you did graph it and we went to the point (-1, 2) what special thing would be happening?

Answer 32

um

Answer 33

let me think a moment

Answer 34

so above those equations represent two lines

Answer 35

yeah

Answer 36

You could easily understand my method. And I showed you the steps so you know they are simple.

Answer 37

i obviously got the answer with eyust's method and not for your method.

Answer 38

we found the point when both lines are equal

Answer 39

oh ok

Answer 40

we found that point!

Answer 41

right when they are equal!

Answer 42

yeah we did

Answer 43

we call this the point of intersection

Answer 44

Which is exactly why when I solve them I write the equations in terms of y first

Answer 45

oh ok eyust

Answer 46

everyone learns math differently... seems like yugo understood this method easier

Answer 47

y= x + 3
y= 2x + 4

Do you realize you can graph both equations on the same graph using a calculator to check your answer?

Answer 48

eyust, let me have a shot please. You've spoke with him all this time.

Answer 49

eyust showed me a process where i understand better than yours. There is nothing wrong with yours either but you have to realize that some people understand different things hero.

Answer 50

I know you want to gloat because you helped him learn your method

Answer 51

lol see ya around guys

Answer 52

haha ok thanks eyust

Answer 53

Yugo, nothing is preventing you from learning my method. If you just understand that when you set both equations equal to y

y = y for example,

you are finding the point where both lines are equal. I know it may seem like my method is difficult to understand, but actually, it is much simpler, and also, the other methods don't always work. You want something that is consistent and my method is much more consistent and reliable.

Answer 54

Thats true and makes since. Can I try an example of your method or use a previous problem