SOLUTION: What formula do i use to solve six problems, who's directions say write the slope-intercept form of an equation of the line that passe through the given point and is perpendicular

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Question 124002: What formula do i use to solve six problems, who's directions say
write the slope-intercept form of an equation of the line that passe through the given point and is perpendicular to the graph of each equation.?
and the formula that i use do i work the problems as i would for the problems that say write the slope-intercept form of an equation of the line that passe through the given point and is parallel to the graph of each equation.?
here's a few problems for example
(-2,-2) y=-1/3x+9
(-4,-3) 4x+y=7
(2,4) x-6y=2
(-4,1) 4x+7y=6
(4,-5) 2x-5y=-10
need help ASAP
thanks
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
Yes, you do it exactly the same way except that when you do parallel lines, the slopes are equal, but when you do perpendicular lines, the slopes are the negative reciprocal of each other. In other words, if m%5B1%5D is the slope of line L%5B1%5D and m%5B2%5D is the slope of line L%5B2%5D, L%5B1%5D is perpendicular to L%5B2%5D if and only if m%5B1%5D=-1%2Fm%5B2%5D

For your first problem:
(-2,-2) y=-1%2F3x%2B9, the slope is -1%2F3, so the slope of the perpendicular has to be 3.

y-y%5B1%5D=m%28x-x%5B1%5D%29
y-%28-2%29=3%28x-%28-2%29%29
y%2B2=3%28x%2B2%29
y%2B2=3x%2B6
y=3x%2B4

Let me know if you need more help.

John