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Write an equation for the line that is perpendicular to Y=-3/7x+4 and passes through (-4,-5)

User Azu
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1 Answer

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Answer:

y = 7/3x +13/3

Explanation:

The equation of the given line is in slope-intercept form (y=mx+b), so we can see the slope (m) is -3/7. The slope of the perpendicular line is the opposite reciprocal of this, so is ...

m = -1/(-3/7) = 7/3

The y-intercept of the perpendicular line can be found from ...

b = y -mx

b = -5 -(7/3)(-4) = -15/3 +28/3 = 13/3

Then the slope-intercept equation of the perpendicular line is ...

y = mx +b

y = 7/3x +13/3

_____

Additional comment

You can get there a little faster using the point-slope form of the equation of a line. For slope m and point (h, k) that form is ...

y -k = m(x -h)

For our perpendicular line, the equation is ...

y +5 = 7/3(x +4)

Write an equation for the line that is perpendicular to Y=-3/7x+4 and passes through-example-1
User Oscar Acevedo
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