Question

Polpak, please help me, I need help big time!

Answer 1

/: Help ?

Answer 2

yes..whats your question?

Answer 3

I have to find the slope and yintecept of two segments, and I need to show inequalites that will show the same soordinates

Answer 4

Coordanates

Answer 5

Interesting...so can you give the equations of the two segments?

Answer 6

Or was there any other info given?

Answer 7

I have to coordniates

Answer 8

the*

Answer 9

slope (m)
\[m = \frac{y2-y1}{x2-x1}\]
y-intercept (b)
\[y = mx +b\]

Answer 10

Yeah dumbcow is right use the slope formula to figure out slope of the line with the coordinates given

Answer 11

Use points as x,y values
point 1: (x1,y1)
point2: (x2,y2)

Answer 12

AB (0,5) (4,5) BC (4,5) (2,3) CA (2,3) (0,5) I would but I dont know how to do that

Answer 13

wait, this makes a triangle
what is the question again?

Answer 14

I have to have inequalties that define each segment

Answer 15

oh ok
yeah you have to put each segment in slope intercept form
y=mx +b
then determine if the inside of triangle is above or below the line

Answer 16

you should first draw out the segments so you can see the triangle

Answer 17

I did , I have it already....

Answer 18

ok
i'll do the 1st one for you

Answer 19

AB (0,5), (4,5)
point 1 (0,5) --> x1 = 0, y1 = 5
point 2: (4,5) --> x2 = 4, y2 = 5
\[m = \frac{y2-y1}{x2-x1} = \frac{5-5}{4-0} = 0\]
y = mx + b
Using point 1, x =0, y=5
5 = (0)(0) + b
5 = b

y = 5
triangle is below this line so make inequality less than or equal
y <= 5

Answer 20

do the other 2 in the same way

Answer 21

dumbcow when I graphed it I got the triangle directly on the line y = 5

Answer 22

Soo... (4,5) (2,3)
Pouint 1 (4,5) --> x1 = 4 y1 = 5
Point 2 (2,3) ->> x2= 2 y2= 3

\[m = \left(\begin{matrix}y2-y1 \\ m2-m1\end{matrix}\right) ---\left(\begin{matrix}3-5\\ 2-4\end{matrix}\right)\]

Answer 23

yes the side of the triangle is on the line y=5 but the area inside triangle can be described only if y<=5

Answer 24

I get it know

Answer 25

good so far

Answer 26

This is what I got

Answer 27

And now Im lost on what to do

Answer 28

And now Im lost on what to do

Answer 29

keep computing m
3-5 = -2
2-4 = -2
then divide

Answer 30

0?

Answer 31

-2/-2 = ?

Answer 32

1

Answer 33

good
so the slope = 1
now use equation
y=mx+b
pick a point to use for x,y values and m=1

Answer 34

How do I uhm .. Do the equation for the inequality?

Answer 35

solve for b first

Answer 36

??????

Answer 37

we have write the line segment in slope-intercept form
slope-intercept form is
y = mx +b
m =slope
b = y-intercept
we solved for slope and got m=1
now solve for b
lets use point (2,3) -> x=2,y=3
3 = (1)(2) + b
can you solve for b now?

Answer 38

Uhm.. 2?

Answer 39

1!!!!!

Answer 40

1!!!!!

Answer 41

haha
yes 3-2 = 1
good job

ok so now we have equation
y = x+1
is triangle above or below this line

Answer 42

Above?

Answer 43

yep
so what should the inequality be?

Answer 44

y >= x+1

Answer 45

perfect
now 1 more to go

Answer 46

Help me through it?

Answer 47

Help me through it?

Answer 48

ok you find the slope and we'll go from there

Answer 49

Hold on, Im trying to write what I have so far

Answer 50

Hold on, Im trying to write what I have so far

Answer 51

Point 1: (2,3) --> x1= 2 y1= 3
Point 2: (4,5) ---> x2= 2 y2= 5

Answer 52

wait we just did this one
(2,3) (0,5)

Answer 53

Noo we did 4,5 2,3

Answer 54

Noo we did 4,5 2,3

Answer 55

Nvmd ... Okay

Answer 56

m= y2-y1/ x2-x1 ----> 5-3/0-2

Answer 57

2/-2 = ...?

Answer 58

yes

Answer 59

-1

Answer 60

-1

Answer 61

yep

Answer 62

Soo wha now?

Answer 63

we have to find y-intercept
y=mx+b
use point (0,5) m = -1
solve for b

Answer 64

I forgot how :P

Answer 65

just plug in what you know
m=-1
x = 0
y=5

Answer 66

5= -1+0
So it would be 6?

Answer 67

mx means m*x --> (-1)(0) = 0

Answer 68

So b - 5

Answer 69

b = 5

Answer 70

yep b=5
also notice on your graph this line segment crosses y-axis at y=5 right?

Answer 71

yes

Answer 72

thats what "b" is, the point where the line crosses y-axis

Answer 73

ok so whats the equation of this line
and is triangle above or below

Answer 74

idk the equation but its but its below?

Answer 75

equation
y=mx +b (memorize this)
plug in m and b that we solved for

Answer 76

im confused

Answer 77

whats confusing
what is m?
what is b?

Answer 78

m slope
y yintercept

Answer 79

good
and what values do we find

Answer 80

m=-1
x = 0
y=5

Answer 81

yes
and b = 5 too

so
y = -1x + 5

Answer 82

see where -1 and 5 replaced m and b

Answer 83

y >= -1x+5?

Answer 84

perfect
you changed your answer, it is actually above

Answer 85

so the inequality I wrrote is right? I gave youu a medal (:

Answer 86

yes
if you draw a vertical line through the line segment, if the triangle part is above intersection point then inequality is ">"

Answer 87

now you are done
The points inside triangle are the only points which satisfy all 3 of these inequalities
hopefully you understand writing an equation of a line given 2 points a little better