Law of Cosines Formula

Given the Law of Cosines formula \(a^2=b^2+c^2-2bc\cos A\), solve for \(a\).

Given the Law of Cosines formula ,solve for .NOTE THAT THERE ARE 2 CORRECT CHOICES. One choice results from isolating on the right side of the equation, while the other choice results from isolating on the left side of the equation. To get on the left side of the equation, we need to add to both sides of the equation.

Find the length of Side BC.

Find AB

Which Law would you use?

• Law of Sines

• Law of Cosines

• Law of the Jungle

• Law of Gravity

Find XZ

• 16.004 meters

• 544.165 meters

• 34.7 meters

• 1204.165 meters

Which Law would you use?

• Law of Sines

• Law of Cosines

• Law of the Jungle

• Law of Gravity

What is the distance across the river? The two sides are 4.15 miles and 5.33 miles. The included angle measure is 37 degrees.

• 2.9 miles

• 3.2 miles

• 3.6 miles

• 3.9 miles

A pilot flying over Norfolk airport is told he will have to redirect and land in either Richmond or Raleigh. Due to air traffic, he is then told he must land in Raleigh. Find the distance he will travel.

• 143 miles

• 127 miles

• 151 miles

• 160 miles

Which Law would you use? (a)  

• Law of Sines

• Law of Cosines