Lesson 5 6 Parallel and Perpendicular Lines Parallel

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Lesson 5. 6 Parallel and Perpendicular Lines § Parallel lines have the same slope

Lesson 5. 6 Parallel and Perpendicular Lines § Parallel lines have the same slope § Perpendicular lines are opposite reciprocals. To find their slopes, you flip the number and change the sign.

Write the slope-intercept form of an equation for the line that passes through (4,

Write the slope-intercept form of an equation for the line that passes through (4, – 2) and is parallel to the graph of The line parallel to Replace m with point-slope form. has the same slope, and (x, y) with (4, -2) in the

Point-slope form Replace m with y with – 2, and x with 4. Simplify.

Point-slope form Replace m with y with – 2, and x with 4. Simplify. Distributive Property Subtract 2 from each side.

Write the equation in slopeintercept form. Answer: The equation is

Write the equation in slopeintercept form. Answer: The equation is

Check You can check your result by graphing both equations. The lines appear to

Check You can check your result by graphing both equations. The lines appear to be parallel. The graph of passes through (4, – 2).

Write the slope-intercept form for an equation of a line that passes through (4,

Write the slope-intercept form for an equation of a line that passes through (4, – 1) and is perpendicular to the graph of Step 1 Find the slope of the given line. Original equation Subtract 7 x from each side. Simplify.

Divide each side by – 2. Simplify. Step 2 The slope of the given

Divide each side by – 2. Simplify. Step 2 The slope of the given line is So, the slope of the line perpendicular to this line is the opposite reciprocal of or

Step 3 Use the point-slope form to find the equation. Point-slope form and Simplify.

Step 3 Use the point-slope form to find the equation. Point-slope form and Simplify. Distributive Property

Subtract 1 from each side. Simplify. Answer: The equation of the line is

Subtract 1 from each side. Simplify. Answer: The equation of the line is

Check You can check your result by graphing both equations on a graphing calculator.

Check You can check your result by graphing both equations on a graphing calculator. Use the CALC menu to verify that passes through (4, – 1).

Write the slope-intercept form for an equation of a line perpendicular to the graph

Write the slope-intercept form for an equation of a line perpendicular to the graph of and passes through (0, 6). Step 1 Find the slope of Original equation Subtract 5 x from each side. Simplify.

a. Write the slope-intercept form of an equation for the line that passes through

a. Write the slope-intercept form of an equation for the line that passes through (2, 3) and is parallel to the graph of b. Write the slope-intercept form for an equation of a line that passes through (– 3, 6) and is perpendicular to the graph of c. Write the slope-intercept form for an equation of a line perpendicular to the graph of and passes through the x-intercept of that line.