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find the equation of the line passing through the given point and perpendicular to the given equation write your answer in slope intercept form

find the equation of the line passing through the given point and perpendicular to-example-1
User Wizche
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1 Answer

4 votes

Slope-intercept form:

y = mx + b "m" is the slope, "b" is the y-intercept


For lines to be perpendicular, their slopes have to be the opposite/negative reciprocals (flipped sign and number)

For example:

slope is 2

perpendicular line's slope is -1/2

slope is -2/3

perpendicular line's slope is 3/2



3.) y = 2x - 2

The given line's slope is 2, so the perpendicular line's slope is -1/2


y=-(1)/(2)x+b To find "b", plug in the point (-5 , 5) into the equation


5=-(1)/(2)(-5)+b


5=(5)/(2)+b Subtract 5/2 on both sides


5-(5)/(2)=b Make the denominators the same


(10)/(2)-(5)/(2)=b


(5)/(2)=b



y=-(1)/(2)x+(5)/(2)



4.) -6x + 5y = -10 Get "y" by itself, add 6x on both sides

5y = -10 + 6x Divide 5 on both sides


y=-2+(6)/(5)x

The given line's slope is 6/5, so the perpendicular line's slope is -5/6.


y=-(5)/(6)x+b Plug in (-2, 5)


5 = -(5)/(6)(-2)+b


5=(10)/(6)+b\\ 5=(5)/(3)+b Subtract 5/3 on both sides


5-(5)/(3) =b Make the denominators the same


(15)/(3)-(5)/(3)=b\\(10)/(3) =b



y = -(5)/(6)x+(10)/(3)



7.) Perpendicular line's slope is -2

y = -2x + b Plug in (1,4)

4 = -2(1) + b

4 = -2 + b

6 = b


y = -2x + 6



8.) Perpendicular line's slope is -1/4


y = -(1)/(4)x+b Plug in (-5 , 2)


2=-(1)/(4)(-5)+b


2 = (5)/(4)+b Subtract 5/4 on both sides


2-(5)/(4)=b Make the denominators the same


(8)/(4)-(5)/(4)=b


(3)/(4)=b



y=-(1)/(4)x+(3)/(4)

User Prasoon Joshi
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