Which of the following is true for the given triangle?
$\cos\theta=\frac{b^2+a^2-c^2}{2bc}$cosθ=b2+a2−c22bc
$\cos\theta=\frac{b^2+c^2-a^2}{2bc}$cosθ=b2+c2−a22bc
$\cos\theta=\frac{b^2+c^2-a^2}{2ab}$cosθ=b2+c2−a22ab
$\cos\theta=\frac{a^2+c^2-b^2}{2bc}$cosθ=a2+c2−b22bc
To use the cosine rule to find the length of $AC$AC, which angle would need to be given?
Find the length of $a$a using the cosine rule.
Round your answer to two decimal places.
Find the length of $a$a using the cosine rule.
Round your answer to two decimal places.