LESSON SEVENTEENTH.
REVIEW.
Read thirteen or more angles whose vertices are at c. (Diagram [15].)
Read four obtuse angles.
Read two right angles.
What three acute angles equal one right angle?
Which is greater, the right angle 4, or the right angle 5?
The obtuse angle 6, or the acute angle 7?
Read twelve pairs of adjacent angles formed by the lines w x, &c.
Read six pairs of vertical angles formed by the same lines.
Read all the interior angles formed by the lines i j, k l, and m n.
Read all the exterior angles formed by the same lines.
Two pairs of opposite exterior angles.
Two pairs of opposite interior angles.
Four pairs of opposite exterior and interior angles.
Two pairs of alternate interior angles.
Two pairs of alternate exterior angles.
Why are the angles i o m, m o j, called adjacent?
What are adjacent angles?
What kind of an angle is i o m? Why?
What is an acute angle?
What kind of an angle is m o j? Why?
What is an obtuse angle?
Why are a c f, f c b, right angles?
What is a right angle?
Why are m o i, j o p, vertical angles?
What are vertical angles?
Why is m o i an exterior angle?
What is an exterior angle?
Why is j o p an interior angle?
What is an interior angle?
Why are m o i, o p k, opposite angles?
What are opposite angles?
Why are j o p, o p k, alternate angles?
What are alternate angles?
