Question

What is the solution to the system?

Line 1
x y
–1 9
3 –3
Line 2
x y
–1 –1
2 5
( _ , _ )

Answer 1

use the equation of a line formula
y=mx+b

Answer 2

where m is the slope and b is the y-intercept

Answer 3

find the equation for the first line

Answer 4

Ok. I'm working on it

Answer 5

@10115658 Y= -3x + 9

Answer 6

@10115658 Thank you. I think I have figured it out.

Answer 7

sorry, i was afk.
give me a sec

Answer 8

ok

Answer 9

I got y=-3x+6

Answer 10

How did you get the 6?

Answer 11

y=-3x+b
plug in a point and solve for b

Answer 12

9=-3(-1)+b

Answer 13

9=3+b
b=6

Answer 14

I'm confused

Answer 15

I think I got it, b/c I lost you for a sec

Answer 16

ok, tell me what your answer is and i'll see what i get

Answer 17

ok, I figured it out

Answer 18

I'm trying to solve still.

Answer 19

I think it's 3. What do you think it is?

Answer 20

what is 3?

Answer 21

x

Answer 22

you should get a point x,y

Answer 23

thats not what i got for x

Answer 24

I'll try again with a point.

Answer 25

Do you want me to show you how i got to my answer?

Answer 26

Yes please

Answer 27

ok, so i found the equation for the first line as y=-3x+6, which i showed you previously

Answer 28

Yeah

Answer 29

the equation for the second line is y=2x+1, using the same method as the equation for the first line

Answer 30

now we need to find what x and y are

Answer 31

so we replace y in the first equation with 2x+1 and solve for x

Answer 32

2x+1=-3x+6

Answer 33

Ok I was trying to figure out x and y too.

Answer 34

solving for x i got
x=1

Answer 35

Then replace x with 1 in one of the equations to find y

Answer 36

y=2(1)+1

Answer 37

y=3

Answer 38

so the point is (1,3)

Answer 39

Do you agree with the answer?

Answer 40

Ok, but wouldn't be 9 though,b/c of the y-intercept.

Answer 41

B I mean

Answer 42

what do you mean? are you talking about the equation for the first line?

Answer 43

Yes

Answer 44

ok, theres an easy way to see if the equation is correct or not

Answer 45

so you think the equation is y=-3x+9 correct?

Answer 46

Yeah

Answer 47

ok, so you plug in a point and see if both sides of the equation are equal

Answer 48

lets plug in -1,9

Answer 49

Ok

Answer 50

9=-3(-1)+9

Answer 51

does 3(-1)+9 equal 9?

Answer 52

Not equal

Answer 53

so that equation is incorrect
lets try my equation

Answer 54

9=-3(-1)+6

Answer 55

Yeah lets try it

Answer 56

9=9
so the equation works

Answer 57

Yeah the equation works

Answer 58

so you understand now?

Answer 59

Yes thank you for helping me. I gave you a medal and became a fan.

Answer 60

https://www.wolframalpha.com/input/?i=y%3D-3x%2B6+%2C+y%3D2x%2B1

Answer 61

thats a nice visual representation

Answer 62

It is. It helped.

Answer 63

cool

Answer 64

Yeah thanks. I appreciate it.