# Write the equatiion of the line that passes through (-1,3) that is perpendicular to the line y = -1/4x+4

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The product of the slope of two perpendicular lines is -1. The slope of the line y = (-1/4)x + 4 is (-1/4), a line perpendicular to this line has a slope of 4.

As the required line passes through the point (-1, 3)

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

=> y - 3 = 4x + 4

=> 4x - y + 7 = 0

**The equation of the line perpendicular to y = (-1/4)x + 4 and passing through the point (-1, 3) is 4x - y + 7 = 0**

because they are perpendicular the slope of the line is 4.

let's call the slope of the first line is m1 (which is -1/4) and the slope of the second line is m2 (which is 4)

** m1*m2=-1**

(-1/4)*m2=-1

m2=4* y=m2x+n*

=> y=4x+n

we know that this line (the second one) passes through (-1,3)

=> 3=4*(-1)+n

3=-4+n

n=7

=>y=4x+7