Question

find an equation of the line containing the given pair of points
(-7,-9) and (-1,-8)

Answer 1

slope = [y(2)-y(1)]/[x(2)-x(1)] find the slope first. post it here and i'll give you the next part.

Answer 2

1x-1y?

Answer 3

for our x and y values we are going to use the points from above, lets make (-7,9) point number 1 and (-1,-8) point number two. so our points are set up like this:

point 1 = (x(1),y(1)) = (-7,-9)
point 2 = (x(2),y(2)) = (-1,-8)

so using that data, and plugging it into the equation above, we get:

[(-8)-(-9)]/[(-1)-(-7)]

when we solve that out it will give us:

-8+9/(-1+7) =
1/6

so the slope is 1/6. normally the slope won't have any variables in it.

Answer 4

next we want to find the y-intercept. since we need that to put into our equation for the line. the equation for the line is y=mx+b. where m is the slope and b is the y-intercept. since we already know the slope, lets put that in:

y=(1/6)x+b

Answer 5

now we want to find the y-intercept. since we know two points that are on the line, we can just use one of those to find the y-intercept. lets use point 1 which was (-7,-9). since we know that the -7 is the x and the -9 is the y, we will put those into the equation we just wrote down:

-9=(1/6)(-8)+b

now we solve for b:

-9=-(8/6)+b
-9+(8/6)=b
-9+(4/3)=b --reduce the fraction
-(27/3)+(4/3)=b -- multiply the -9 by (3/3) so that we can combine the numbers
-(23/3)=b

now that we know b, we can put our complete equation together:

y=(1/6)x-(23/3)

Answer 6

now use the same method to work another problem!