Question

Choose the equation of the line passing through the point (2, 6) and parallel to y = -3x - 4.

Answer 1

I don't need the answer..well I do but I would like to be explained how to do it. lol

Answer 2

what do you think is the slope of the line y = -3x -4 ?

Answer 3

umm -3 correct?

Answer 4

correct - so if the line you want to find is parallel to y = -3x - 4, then you know it must have the same slope as this.
so now you know that the line has slope -3

Answer 5

next, do you know the general equation of a straight line?

Answer 6

not off the top of my head

Answer 7

you need to know that in order to solve this question. Look back at your class notes or text book to refresh yourself and then come back to this problem.

Answer 8

Ok .

Answer 9

this web site might also help you: http://www.mathsisfun.com/equation_of_line.html

Answer 10

y = mx + b?

Answer 11

Oh! Thank you!

Answer 12

yw :)

Answer 13

But was that right? c;

Answer 14

yes - y = mx + b is indeed the general equation of a straight line.
here "m" represents the slope of the line and "c" represents where it intersects (or crosses) the y-axis.

Answer 15

so in your case, you know that the sope of the line you are looking for is -3, so you know that m=-3, you therefore now know that the equation of the line you want is of the form:\[y=-3x+c\]

Answer 16

you are also told that that this line passes through the point (2, 6). which means that you know that when x=2, y=6. You can use this to get:\[y=-3x+c\]therefore:\[6=-3(2)+c=-6+c\]solve this to find "c" and then you can write the final form for the equation of the line being asked for.

Answer 17

c = 12 ?

Answer 18

correct - so you should now be able to write the equation of the line being asked for.

Answer 19

Oh! I get it now! Thank you!

Answer 20

yw - what answer did you get in the end?

Answer 21

y=-3x + 12

Answer 22

perfect! well done! :)

Answer 23

Thanks! Thank you once again!

Answer 24

np - yw :)