Identifying Parallel and Perpendicular Lines

Which of the following graphs shows perpendicular lines?

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Slopes of parallel lines are...

• opposite reciprocals.
• opposites.
• the same.
• always 7.

Use this formula to find the...?

• Area of a square

• slope of a line

• distance between two pints

• not a real formula

Two lines are parallel if they have the same??

Find the slope of the line through each pair of points.

(8, 4) and (2, 6).

• m = 1

• m = -1

Find the slope of the line through each pair of points.

(-22, 9) and (5, -9).

• Undefined

• m = 0

• m = -2