Law of Sines and Law of Cosines

Which is the smallest angle in this triangle?

• ∠A

• ∠B

• ∠C

Tags

CCSS.HSG.CO.C.10

Which of the following formulas shows the Law of Cosines?

• $c^2=a^2+b^2-4\left(a\right)\left(b\right)\cos\left(A\right)$
  

• $2c=2a-2b-2\left(a\right)\left(b\right)\cos\left(C\right)$
  

• $c^2=a^2+b^2-2\left(a\right)\left(b\right)\cos\left(C\right)$

• $\frac{a}{\cos\left(A\right)}=\frac{b}{\cos\left(B\right)}$
  

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Which Law would you use?

• Law of Sines

• Law of Cosines

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Which Law would you use?

• Law of Sines

• Law of Cosines

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Which tool can be used to solve for the missing angle?

• Law of Sines

• Law of Cosines

• Sine, Cosine or Tangent

• cannot be solved with given information

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Which tool can be used to solve for the length BC?

• Law of Sines

• Law of Cosines

• Sine, Cosine or Tangent

• cannot be solved with given information

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

What tool can be used to solve for side x?

• Law of Sines

• Law of Cosines

• Sine, Cosine or Tangent

• cannot be solved with given information

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Choose the correct setup.

• $x^2=3^2+4^2-2\left(3\right)\left(4\right)\cdot\cos\left(65\right)$

• $x^2=3^2+4^2-2\left(3\right)\left(4\right)\cdot\sin\left(65\right)$
  

• $65^2=3^2+4^2-2\left(3\right)\left(4\right)\cdot\cos\left(x\right)$
  

• $\frac{\sin65}{3}=\frac{\sin\left(x\right)}{4}$
  

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Solve for x

• 3.85

• 4.25

• 3.35

• 5.65

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

Choose the correct setup.

• $\frac{\sin\left(29\right)}{50}=\frac{\sin\left(37\right)}{A}$
  

• $\frac{\sin\left(50\right)}{37}=\frac{\sin\left(A\right)}{29}$
  

• $\frac{\sin\left(50\right)}{29}=\frac{\sin\left(A\right)}{37}$

• $A^2=29^2+37^2-2\left(29\right)\left(37\right)\cdot\cos\left(50\right)$
  

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11