*I will
begin with a review of the Angle-Angle-Side Congruence Theorem
and why it works. I will go over their homework and any questions
they may have on it. I will do a few review problems covering
Angle Angle Side Congruence.*

Okay class, what is the Congruence Theorem that doesn't work in most cases and that spells a word we don't use at school?

SSA, yes!

I have been telling you that this case doesn't work, right? I am going to show you why it doesn't work in most cases.

*I will
draw the picture on the board and lead them into the discovery
that the SSA case works only in special cases, when you are dealing
with right triangles.*

So, a
special case of SSA does work, right? This case deals only with
right triangles and is called the **Hypotenuse Leg Theorem.**

__What
is right triangle?__

*A triangle
that has a 90 degree angle in it.*

__What
is a hypotenuse?__

*the
side opposite the right angle*

__What
are the legs?__

*the
sides opposite the acute angles in a right triangle*

*(I
will make sure to right these definitions on the overhead for
them to copy down.)*

*We
will do some examples to make sure they understand the distinction
between hypotenuse and legs of a right triangle and make sure
they realize these only apply to right triangles.*

Okay,
so the * Hypotenuse Leg Theorem* says that if you have
a hypotenuse and one leg of a right triangle congruent to the
hypotenuse and leg of another right triangle, then the triangles
are congruent.

*We
will practice doing some examples involving the Hypotenuse Leg
congruence case. I will emphasize to the students that every time
you see two right triangles that look congruent, you can't just
assume that they are congruent by Hypotenuse Leg, but that you
could have Side-Angle-Side Congruence for two right triangles,
etc. I will again reemphasize how the ORDER MATTERS when stating
two triangles congruent but that it doesn't matter when labeling
segments or angles. If time permits, we will throw in some other
Angle-Angle-Side Congruence examples. Near the end of class, I
will pass out a Section 5.7 worksheet for them since we have completed
this section now. I will explain to them how it covers proving
triangles congruent using the Angle-Angle-Side Congruence Theorem
and the Hypotenuse Leg Congruence Theorem.*

*I will
summarize by revisiting what a hypotenuse and leg is of a right
triangle. I will restate what the HL Theorem is and how it is
a special case involving right triangles when the SSA case does
work.*