Math help...equations of a line and stuff?

Question

can you guys give me the steps to solve these questions? my first question is :

given points A(-3, 2), B(6,8), and C(-4,6), determine the coordinates of a point D on the y axis so that CD is parallel to AB.

i dont really know what to do after finding the slope?

and this other question i dont get.

Find the value of k if the slope of kx-3y= -9 is 1/9

thanks loots

Answer 1

for the line containing a and b

y = mx + b

m = (2-8)/(-3-6) = (-6)/(-9) = 2/3

you need not concern yourself with b but you can calculate it if you would like

Now for a line containing c and d to be parallel to the one containing a and b they have to have the same slope or

y = (2/3)x + b and determine the intercept, b using point c where
6 = (2/3)(-4) + b

Answer 2

Last question first.

kx - 3y = - 9

-3y = - kx - 9

y = kx/3 + 3

Now the equation is in standard form of y = mx + c

m = k/3 = 1/9

k = 1/3

Now let us do the first question.

First find the equation of AB and then look for D so that the slopes of AB and CD are same.

Answer 3

try ur own