Chapter 12.6, Problem 2OE

To determine

To use the law of cosines to give an equation involving the side or angle labeled $x$

Answer to Problem 2OE

  $\cos x=\frac{5^2+5^2-{11}^2}{2\left(5\right)\left(5\right)}$

Explanation of Solution

Given information :

  

Cosine formula states that,

  $\cos A=\frac{b^2+c^2-a^2}{2bc}$

Hence we put the values given,

  $\cos x=\frac{5^2+5^2-{11}^2}{2\left(5\right)\left(5\right)}$

Hence this is the required equation.