HOW DO YOU DO THIS QUESTION?
Choose the equation of the line passing through the point (-4, -2) and parallel to y = x + 2.

Question

HOW DO YOU DO THIS QUESTION?
Choose the equation of the line passing through the point (-4, -2) and parallel to y = x + 2.

anonymous · Answer

First off, what will the slope of a line that is parallel to y=x+2 be?

anonymous · Answer

they have the same slope

anonymous · Answer

Good, do you know how to use the point slope formula?

anonymous · Answer

$$y-y _{1} = m(x-x _{1})$$

anonymous · Answer

yea i think so

anonymous · Answer

Y-(-2)=1(X-(-4))

anonymous · Answer

Cool, now solve for y.

anonymous · Answer

the equation for the question is y=1/4x +2

anonymous · Answer

sorry!

anonymous · Answer

Same principle.  You know the slope will be the same.

You've got a point on the line.

Just plug and chug.  :)

anonymous · Answer

That makes more sense cause the other one would give you the same equation

anonymous · Answer

The trickiest part of these is generally making sure that you change the signs as needed.

anonymous · Answer

Yeah, I noticed that.  I thought it might have been a trick question.

anonymous · Answer

is it Y-(-2)=1/4 (X-(-4)?

anonymous · Answer

Yup.  Now just solve for y.

anonymous · Answer

okk thanks alot

anonymous · Answer

No problem.  Please not that doing this for a line that was perpendicular is almost exactly the same, you've just got to find the slope of the new line.

Remember when lines are perpendicular:

$$m _{1} \times m _{2} = -1$$

anonymous · Answer

is it  y = 1/4x - 3

anonymous · Answer

I'm getting y = 1/4x - 1

anonymous · Answer

?????:(

anonymous · Answer

Here's our point slope formula again:
$$y-(-2)=1/4 (x-(-4)$$

Distribute the 1/4:
$$y+2=1/4x +1$$

Subtract 2 from both side:
$$y=1/4x -1$$

anonymous · Answer

Gotta watch those sign changes :)

anonymous · Answer

oh ok i get it yea i messed up with the signs but thanks alot :))))))))))))))))))))))))

anonymous · Answer

Not a problem.  :D  Good luck!

anonymous · Answer

Choose the equation of the line passing through the point (-4, -2) and perpendicular to y = -x + 6. is the answer to this y = -x +2??

anonymous · Answer

The slope of a line perpendicular to y = -x + 6 is m=1.

To get that, take the original slope, flip it upside down, and reverse the sign.

anonymous · Answer

oh yea i forgot about that

anonymous · Answer

I've got to run, but just to make sure you've got it.

m=1

$$y-(-2)=1(x-(-4))$$
$$y+2=x+4$$
y=x+2