Question

I need an equation that represents the line that passes through the points (6, –3) and (–4, –9)? Thank in advance!

Answer 1

a line has form y=mx+b
where m is the slope and b is the y-intercept
these are the two things we need to find

Answer 2

do you know how to find the slope?

Answer 3

yes

Answer 4

so what is the slope here?

Answer 5

1,4?

Answer 6

\[m=\frac{ changey}{change x}=\frac{-3-(-9)}{6-(-4)}\]

Answer 7

thats not what i spelled lol

Answer 8

m=(change in y)/(change in x)

Answer 9

i see

Answer 10

\[m=\frac{-3+9}{6+4}=\frac{6}{10}=\frac{3}{5}\]

Answer 11

ok well that helps a bit

Answer 12

so now we can fill in one blank
so we have
\[y=\frac{3}{5}x+b\]
so b is the only thing left to find

Answer 13

Use a point given to you in plug in that point to find b

Answer 14

like plug in x=6 and y=-3 (this is a point given to you)
and now solve for b

Answer 15

i must go so maybe someone else can check your answer when you get it

Answer 16

-5 give or take?

Answer 17

well thanks...alot

Answer 18

\[-3=\frac{3}{5}(6)+b\]

Answer 19

\[-3-\frac{18}{5}=b\]

Answer 20

\[b=\frac{-3(5)}{5}-\frac{18}{5}=\frac{-15}{5}-\frac{18}{5}=\frac{-23}{5}\]

Answer 21

so i go now
you have all the pieces of the puzzle now just put them in the right spot in you are done

Answer 22

ok cool thanks for writing it out rather than just throwin out the answer cuz it helps me learn

Answer 23

Another way of looking at it:
If you have 2 points (6, –3) and (–4, –9),
you can plug this in the equation y=mx+b to get 2 equations:\[-3=6m+b\]\[-9=-4m+b\] solve the simultaneous equations for m & b