Question

Write an equation that passes through the points (4,-1) and
(2,- 2).

Answer 1

use the formula :
(y-y1)/(y2-y1) = (x-x1)/(x2-x1)

Answer 2

-1/-2

Answer 3

i did, y2-y1/x2-x1

Answer 4

yes, that's just for the slope not whole like ur question ask

Answer 5

lol i dont understand the y-y1 part .... does that mean y-(-1)/-2-(-1) ?

Answer 6

@RadEn That equation above is new to me! O.o but awesome! thanks for posting that!

Answer 7

well, another way is use the formula of a straight line :
y = mx + c (with m is the slope)
you got m = 1/2, put m = 1/2 into equation above :
y = 1/2 x + c

then take one of the points given above, let it is point (4,-1)
subtitute that point then solve for c

y = 1/2 x + c
-1 = 1/2 * 4 + c
-1 = 2 + c
c = -3

finally, we have an equation completely it is y = 1/2 x - 3

Answer 8

WOAH! thats a brain scrambler hahah, thanks for helping me out. You might need to stick around more. :D

Answer 9

really, i got it in my book since 20 year ago, lol
@johnweldon1993

Answer 10

haha, no the way I learned was to find the slope (y2-y1)/(x2-x1) then plug that into the point slope formula....

now, mind = blown! haha thanks for that :D wonder what else I've missed lol

Answer 11

hehe, thanks :)

Answer 12

Now I'm going to go through my calc books again and make sure I'm not overlooking something that would make life 20X easier! haha

Answer 13

:)