standard_description: Explain how the criteria for triangle congruence (ASA, SAS, and SSS) follow from the definition of congruence in terms of rigid motions.
problem_activity: Problem 1
Find
$${\mathrm{sin}(u-v)}$$
given
$${\mathrm{sin}(u)={8\over17}}$$
with
$${0\leq u \leq {\pi\over2}}$$
and
$${\mathrm{cos}(v)=-{24\over25}}$$
with
$${\pi \leq v \leq {3\pi\over2}}$$
.
Problem 2
Evaluate:
$${\mathrm{sin}(-15^{\circ})}$$
$${\mathrm{cos}(15^{\circ})}$$


aligns: no