Question

Ax+By=C what is the result if A=0

Answer 1

umm
if you plug in 0 for A
then (0)x + By = C
so By = C then divide both sides by B
so that y = C/B

Answer 2

Thankss !

Answer 3

you're welcome :)

Answer 4

What it'd be if B=0?

Answer 5

same idea :)
if you plug in 0 for B
then Ax + (0)y = C
so Ax = C then divide both sides by A
so that y = C/A

Answer 6

Oh I knew that...... :\ what kind of graph would it be tho ?

Answer 7

if A = 0 it would be y = something
so it would be a horizontal
if B = 0 it would be x = something
so it would be vertical

Answer 8

OMG Thankss ! :D

Answer 9

you're welcome :)

Answer 10

Do you know this if the x-intercept of the graph of 2x+6y=4 is 2 is that true or false ?

Answer 11

x intercept is when y = 0
so when you plug in 0 for y
2x + 6(0) = 4
so 2x = 4 then divide both sides by 2
so x = 2

Answer 12

Thanks !! sorry if i ask to much ! but do you know .. If the y-intercept of the graph of x-2y=7 is 3.5

Answer 13

y intercept is when x = 0
so plug in 0 for x
so (0) - 2y = 7
-2y = 7 then divide both sides by -2
so y = -7/2 = negative 3.5

Answer 14

Thankss !!! Can you help me on how to find slope ?...

Answer 15

sure :)
rise ( y2 - y1 )
slope = ----- = ----------
run ( x2 - x1 )
when given points (x1, y1) and (x2, y2)

Answer 16

Yeah like i have the point (-2,5), (8,-4)

Answer 17

ok then
rise ( y2 - y1 ) ( (-4) - (5) ) ( -9 )
slope = ----- = ---------- = ----------- = -----
run ( x2 - x1 ) ( (8) - (-2) ) ( 10 )

Answer 18

if you're wondering where the numbers came from:
(x1, y1) and (x2, y2)
(-2 , 5) and (8 , -4)
^ ^ ^ ^ that's how I matched them up :)

Answer 19

Thanks !! what if the points are (6,-2), (-3,7)

Answer 20

(x1, y1) and (x2, y2)
(6 , -2) and (-3 , 7)
so
rise ( y2 - y1 ) ( (7) - (-2) ) ( 9 )
slope = ----- = ---------- = ----------- = ----- = -1
run ( x2 - x1 ) ( (-3) - (6) ) ( -9 )

Answer 21

Thanks ! how would you write (10,1); m=1/5 in point slope form ?

Answer 22

point slope form: y - y1 = m(x - x1)
when given m = slope and point (x1, y1)
so plug in m = 1/5 and x1=10 and y1=1
into y - (y1) = (m) (x - (x1) )

Answer 23

so it'd be y-(10)=(1/5)(x-1) right ?

Answer 24

close :)
y - (1) = (1/5) (x - 10)

Answer 25

Oh i see I read it wrong lmao

Answer 26

yep ^.^

Answer 27

Yeah how would you write an equation in slope intercept form if the points are (-2,2) and (2,-8)

Answer 28

well first find the slope :)
give it a try

Answer 29

wait how do we find the slope again i forgot ...

Answer 30

rise ( y2 - y1 )
slope = ----- = ---------- =
run ( x2 - x1 )

Answer 31

when given points (x1, y1) and (x2, y2)

Answer 32

oh yeahh thanks !!

Answer 33

how do you know which one is x1 and x2 and y1 and y2

Answer 34

whatever way it lines up :P
(x1, y1) and (x2, y2)
(-2, 2 ) and ( 2, -8)

Answer 35

Ohhh i feel dumb lmao

Answer 36

lol it's fine :)
just be careful to not mess up that something like 2 - (-2) = 2+2

Answer 37

the slope is -10/4 right ....?

Answer 38

yep! :)
which can be simplified to -2.5

then slope intercept form is y = mx + b
where m = slope
so when m = -2.5
y = -2.5x + b
but then we need to find b

so we temporarily plug in a given point
like (-2, 2)
so 2 = (-2.5)(-2) + b solve for b

Answer 39

how would we solve for b?

Answer 40

2 = (-2.5)(-2) + b
2 = 5 + b then subtract 5 from both sides to get b

Answer 41

so -3=b

Answer 42

yep :)
which we plug back into y = -2.5x + b
to get y = -2.5x - 3
tah-dah! :)

Answer 43

Omg Thankss !! you're like a life saver !!

Answer 44

you're welcome :)

Answer 45

do you know how to find x and y intercepts ?

Answer 46

x intercept is when y = 0
y intercept is when x = 0

Answer 47

oh wait so how'd you find 4x-3y=12 ?

Answer 48

x intercept is when y = 0
so 4x - 3(0) = 12
4x = 12
x = 3 is the x intercept

then y intercept is when x = 0
so 4(0) - 3y = 12
-3y = 12
y = -4 is the y intercept

Answer 49

Oh okay thanks ! how would you like graph an equation if it's like y=-3/4x+2

Answer 50

y intercept would be y = 2
in other words at point (0, 2)
and x intercept would be at x = 8/3
in other words at point (8/3, 0)
you would plot those points on the graph
then draw a line through it :)

Answer 51

Oh okay what if it's 2x+3y=9

Answer 52

y intercept would be y = 3
in other words at point (0, 3)
x intercept would be x = 9/2
in other words at point (9/2, 0)
you would plot those points on the graph
then draw a line through it :)

Answer 53

THANK YOUUU !!!!

Answer 54

you're welcome :)

Answer 55

what if we're doing like slope intercept form but it doesn't show the points like this one x-4y=8

Answer 56

slope intercept form is y = mx + b
so in a sense, it just wants you to get "y" alone then :)
so x - 4y = 8
-4y = -x + 8
y = (1/4)x - 2

Answer 57

Oh how about y-2=5(x-1)

Answer 58

same idea :)
get y alone and simplify

Answer 59

Oh! so it'd be y=5x-1+2 Right...?

Answer 60

remember to distribute the 5 :)

Answer 61

Oh ! so it'd be y=5x-5+2

Answer 62

then add like terms :)

Answer 63

? how would you do that ..? lmao

Answer 64

well you can add -5 + 2 right? :P

Answer 65

I guess lol

Answer 66

so you'll get y = 5x - 3

Answer 67

Oh lmao i'm bad at math as you can see lol

Answer 68

lol you're doing really well compared to some other people I've had to deal with XD trust me :P

Answer 69

how'd you write y=-2x+3 in standard form...? lol sorry if i ask a lot

Answer 70

and lmao really i feel smart and dumb lmao but thanks :)

Answer 71

standard form is ax + by = c
so basically get all the values with variables attached to them to one side
so for y = -2x + 3 just add 2x to both sides :)

Answer 72

Ohh so it'd be 2x+y=3

Answer 73

yep :)

Answer 74

wait so if i do y-4=2(x-1) we distribute the 2 which will now be y-4=2x-2right ? and after that what do we do?

Answer 75

yep :)
then add 4 to both sides
then subtract 2x from both sides :)

Answer 76

y=2x-2+4 right ?

Answer 77

yeah
then subtract 2x from both sides :)

Answer 78

y-2x=2+4 right

Answer 79

then we subtract 4 ?...

Answer 80

mmm
-2x + y = 2
2x - y = -2

Answer 81

Thank Youu !!! :D i felt like you're a better teacher than my math teacher lol like no joke

Answer 82

thanks :) lol

Answer 83

how'd we graph y=lxl-1 ....?

Answer 84

and lmaoo your welcome :)

Answer 85

original graph was https://lh3.ggpht.com/_F6M745sbI3g/TI-Re7FDUwI/AAAAAAAAABM/6Q-oNeWjmxI/s1600/absolute+value.gif
then y = |x| - 1
is that graph shifted down 1

Answer 86

Oh okay Thankss !!

Answer 87

no problem :)