Parallel and Perpendicular Lines

Front

What are the slopes of parallel lines?

Back

The slopes of parallel lines are identical.

Front

What are the slopes of perpendicular lines?

Back

The slopes of perpendicular lines are opposite reciprocals.

Front

Write the equation of a line perpendicular to y = -1/2x + 5/2 that passes through (-4, 5).

Back

y = 2x + 13

Front

Write the equation of a line perpendicular to y = 3x - 8 that passes through (-3, -9).

Back

y + 9 = -1/3(x + 3)

Front

Write the equation of a line parallel to y = -1/2x + 3 that goes through (4, -1).

Back

y + 1 = -1/2(x - 4)

Front

What is the slope of the line y = 2x + 3?

Back

The slope is 2.

Front

If two lines have slopes m1 and m2, when are they parallel?

Back

They are parallel if m1 = m2.

Front

If two lines have slopes m1 and m2, when are they perpendicular?

Back

They are perpendicular if m1 * m2 = -1.

Front

What is the slope-intercept form of a line?

Back

The slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.

Front

How do you find the slope of a line given two points (x1, y1) and (x2, y2)?

Back

The slope is calculated as (y2 - y1) / (x2 - x1).