body{margin:0;} noscript{z-index: 10000; position: fixed; display: block; height: 100%; width: 100%; background: #fff;} noscript .fa{font-size: 40px; display:block; color: #daa520;} noscript div{margin-top: 6%; padding-left: 20px; padding-right: 20px; text-align: center;} ! You must have JavaScript enabled to use this site.

McGraw Hill Glencoe Algebra 1, 2012

MH

McGraw Hill Glencoe Algebra 1, 2012 View details

4. Parallel and Perpendicular Lines

Continue to next subchapter

Exercise 38 Page 243

How do you know if lines are parallel or perpendicular?

Parallel

Practice makes perfect

Lines are parallel if their slopes are exactly the same, and perpendicular if their slopes are negative reciprocals. Any other relationship between the slopes would result in neither parallel nor perpendicular lines. Let's write both equations in slope-intercept form, highlighting their slopes.

Given Equation	Slope-intercept form	Slope
2x+7y=-35	y= -2/7x-5	m_1= -2/7
4x+14y=-42	y= -2/7x-3	m_2= -2/7

Since the lines have equal slopes, we can conclude that they are parallel.

Subchapter links

Check Your Understanding p.242

Practice and Problem Solving p.243-244

H.O.T. Problems p.244

Standardized Test Practice p.245

Spiral Review p.245

Skills Review p.245