5.7 Parallel and Perpendicular Lines Parallel Lines - 2 lines that never intersect They have the same slope m1 = m2 They have different y-intercepts b1 ≠ b2 Perpendicular Lines - 2 lines that intersect They create 4 right angles They have different slopes (m1)(m2) = -1 They can have the same y-intercept
Identify the lines as parallel or perpendicular. Ex A) 2x + 5y = 7 4x + 10y = 18 Line 1 Line 2 2x + 5y = 7 4x + 10y = 18 -2x -2x -4x -4x 5y = -2x + 7 10y = -4x + 18 5 5 5 10 10 10 Parallel
Ex B) Line 1 Line 2 3x + 6y = 8 -3x -3x 6y = -3x + 8 6 6 6 (m1)(m2) = -1 Perpendicular
Write an equation in slope-intercept form that is parallel to the given line and passes through the given point. Ex C) Point-Slope Form Slope-Intercept Form
Write an equation in slope-intercept form that is parallel to the given line and passes through the given point. Ex D)
Point-Slope Form Slope-Intercept Form
Ex E) m= opposite and reciprocal Write an equation in slope-intercept form that is perpendicular to the given line and passes through the given point. Ex E) m= opposite and reciprocal Point-Slope Form Slope-Intercept Form
Write an equation in slope-intercept form that is perpendicular to the given line and passes through the given point. Ex F)
Point-Slope Form Slope-Intercept Form