Examples through Parallel & Perpendicular chathamtownfc.net Topical outline | Geometry rundown | MathBits" Teacher sources Terms the Use contact Person: Donna Roberts

This page will take a look in ~ a few of the various instances that make use of the concept of slopes connected with parallel and perpendicular lines.

You are watching: What type of line is parallel to a horizontal line

inquiries Asking straight for Equations the Parallel or Perpendicular Lines:
 1. What is the equation the a line parallel come y = -4x + 5 and passing through the point (6,-3)?

Solution: The slope of the offered line, y = -4x + 5 is -4 (remember y = mx + b). since parallel lines have actually = slopes, our line has actually a steep of -4. Use the point -slope form of the equation the a line: y - y1 = m(x - x1). m = -4 (x1, y1) = (6,-3) ANSWER: y - (-3) = -4(x - 6) y + 3 = -4x + 24 y = -4x + 21

 2. What is the equation the a heat perpendicular to 2y = x - 4 and passing with the allude (-4,1)?

Solution: The steep of the offered line, 2y = x - 4 is ½ (remember to fix for y first). Due to the fact that perpendicular lines have negative reciprocal slopes, ours line has a slope of -2.Use the point-slope form of the equation of a line: y - y1 = m(x - x1). m = -2 (x1, y1) = (-4,1) ANSWER: y - 1 = -2(x - (-4))y -1 = -2x - 8y = -2x - 7

 concerns Asking Indirectly for Equations the Perpendicular Lines:
 3. What is the equation of a heat tangent to a circle who equation is (x - 5)2 + (y + 2)2 = 25 at the suggest (8,-4), i beg your pardon lies on the circle ?

Solution: The one (x - 5)2 + (y + 2)2 = 25 has actually a center at (5,-2) and a radius that 5. A tangent come a circle is perpendicular to the radius at the point of tangency. Find the steep of the radius:

The slope of the tangent will be