Write the equation of the line in slope-intercept form.
perpendicular to y= 2x+6 and
passing through (-4,2)

Question

Write the equation of the line in slope-intercept form. 
perpendicular to y= 2x+6 and
passing through (-4,2)

mathlegend · Answer

do I still use the point slope form.. formula?

mathlegend · Answer

y-y1=m(x-x1)

anonymous · Answer

yes that is correct and then you substitute the given values.

mathlegend · Answer

Do I keep the slope as 2?

anonymous · Answer

no, slope perpendicular to 2 is -1/2

anonymous · Answer

y = -1/2x

mathlegend · Answer

okay the reciprocal

anonymous · Answer

yup

anonymous · Answer

perpendicular means, the slope for the other line is negative reciprocal

mathlegend · Answer

I got a weird answer...
y = $$\frac{ -1 }{ 2}x$$ + 0

mathlegend · Answer

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mathlegend · Answer

I checked the answer key and it says it is wrong....

anonymous · Answer

plug the values in correctly into the point-slope form

anonymous · Answer

yup it must be y=-1/2x+4

mathlegend · Answer

Yeah that is the answer

mathlegend · Answer

What did you do that I did not do?

mathlegend · Answer

y-2=-1/2(x+4)

anonymous · Answer

$$y-2=m[x-(-4)]$$
the perpendicular slope of 2 is -1/2

mathlegend · Answer

yeah I got that...

anonymous · Answer

i think that the answer in your notes is wrong and it should be y=-1/2x as y=-1/2(x+4)+2 simplifies to y=-1/2x-2+2 thus y=-1/2x

anonymous · Answer

$$y-2=-\frac{ 1 }{ 2 }[x-(-4)]$$

mathlegend · Answer

Oh so I was right...
y=-1/2x + 0

anonymous · Answer

when you add 2 on both sides, what happens to the right side?

anonymous · Answer

it looks like it. The notes went wrong on the substitution. to get the answer that you have in the notes you need to have y=-1/2(x-4)+2

anonymous · Answer

you are correct:
$$y-2+2=-\frac{ 1 }{ 2 }x-2+2$$