CPM Geometry Ch 5 Math Notes 5.3.2-5.3.5 Quiz Practice

True or False: The Law of Sines can only be applied to right triangles.

• True

• False

Answer explanation

Law of Sines CAN be used on right triangles, but it is not the best tool.

For right triangles, you should use SOH-CAH-TOA and Pythagorean Theorem.

True or False: The Law of Cosines can only be applied to right triangles.

• True

• False

Answer explanation

Law of Cosines CAN be used on right triangles, but it is not the best tool.

For right triangles, you should use SOH-CAH-TOA and Pythagorean Theorem.

The Law of Sines is based upon the fact that...

• ... all triangles are similar.

• ... all triangles are congruent.

• ... all sides within a triangle correspond.

• ... in any shape the ratio of a side length to its opposite angle will always be constant.

• ... within a triangle, the ratio of the sine of an angle to the length of the side opposite the angle is constant.

When applying the formula for the Law of Cosines, you must know which of the following.

• two angle measures

• two angle measures and one side length

• three angle measures

• two side lengths and the angle between them OR three side lengths.

Answer explanation

Law of Cosines is best used for SAS or SSS situations.

It is possible to use Law of Cosines for the ambiguous case (ASS or SSA), but Law of Sines is easier in those cases.

Which of the following presentations of information in a triangle is problematic for our triangle tools? (check all that apply)

• SSS

• SSA

• AAA

• SAS

• AAS

Answer explanation

AAA can produce an infinite number of triangles.

SSA (or ASS) is the ambiguous case, producing 0, 1, or 2 possible triangles.