91Ó°ÊÓ

Two skew lines intersect.

Classify each pair of angles as alternate interior angles, same-side interior angles, corresponding angles, or none of these.

and

State the postulate or theorem that justifies each statement.

$∠1â‰\dots ∠5$

If $câˆ\yen d$, name all angels that must be congruent to $∠1$.

In each exercise some information is given. Use this information to name the segments that must be parallel. If there are no such segments, write none.

Look for a pattern and predict the next two numbers in each sequence.$18,\text{ â¶Ä‰}15,\text{ â¶Ä‰}12,\text{ â¶Ä‰}9,\text{ â¶Ä‰}\mathrm{....}$

Fill in the following blanks.

If a triangle has no congruent sides then the triangle is called __?

Tell whether the reasoning process is deductive or inductive.

KY did his assignment, adding the lengths of the sides of triangles to find the perimeters. Noticing the results for several equilateral triangles, he guesses that the perimeter of every equilateral triangle is three times the length of a side.

Draw a triangle that satisfies the conditions stated. If no triangle can satisfy the conditions, write not possible.

2. a. An acute scalene triangle.

b. A right scalene triangle.

c. An obtuse scalene triangle.

For each statement

1. tell whether the statement is true or false,
2. write the converse,
3. tell whether the converse is true or false.

If two lines are parallel, then they are not skew.