3/27: C&C Trig

If I know the lengths of TWO sides of a RIGHT triangle then I can find the length of the third side.

• TRUE; using Pythagorean Theorem

• False; you would need information on an angle or two.

Find the length of the missing side. 

• 17 cm
• 22 cm
• 15 cm
• 13 cm

Find the length of the missing side. 

• 20 in.
• 68 in.
• 16 in.
• 80 in.

Focus in on the 70^o angle...which two sides are "identified" in the figure?

• opposite

  (an unknown)

• hypotenuse

  (4 units)

• adjacent

  (no marking)

• None of these

So we should have found;

opposite side = ?

hypotenuse = 4

(remember...related to the 70^o angle!!!) Which trig ratio uses these two sides?

• sine (sin)

• cosine (cos)

• tangent (tan)

• None of these

• multiply both sides by 4

• divide both sides by 4

• add 4 to both sides

• subtract 4 from both sides

Let's consider angle B (25^o). Which two sides do "b" and "8" represent?

• Opposite

• Adjacent

• Hyptonuse

• All of them

Let's focus on these two;

Opposite Side = "b"

Adjacent Side = "8"

(in relationship to angle B)

Which trig ratio uses these two sides?

• sine (sin)

• cosine (cos)

• tangent (tan)

• none of them

So now...which of the following equations would hold true?