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Write the equation for the line that passes through (2, -4) and is

perpendicular to the line to x - 4y = 7.

1 Answer

4 votes

Answer: y= x-2

Explanation:

Perpendicularity entails the slope of line a is -1 divided by the slope of line b

m1= (-1/m2)

From y=Mx +c

We compare with x-4y=7

y=(1/4)x-7/4

Meaning m2= 1/4

m1= -1/(1/4)= -1*4= -4

((y-y1)/(x-x1))= ((y2-y1)/(x2-x1))=m1

x1= 2, y1= -4

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

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

Cross multiply

y+4= -4(x-2)

y= x-2

User Marty Pitt
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