Question

Calculate cos theta to two decimal places

Answer 1

Answer:

B. 0.72

Step-by-step explanation:

In order to find the answer we need to use the following formula:

$a^2=b^2+c^2-2bc*cos(\theta)$ where:

a, b, c are the length of the sides and $\theta$ the angle, so:

$7^2=10^2+8^2-(2*10*8)*cos(\theta)$

$49=164-(160)*cos(\theta)$

$cos(\theta)=0.71875$

In conclusion, $cos(\theta)=0.72$, so the answer is B.