Question

score: 9/10 current time: 144.5
find: \\( \cos b \\)
the figure is not drawn to scale
answer
\\( \frac { 64 } { 80 } \\) \\( \frac { 48 } { 64 } \\) \\( \frac { 64 } { 48 } \\) \\( \frac { 48 } { 80 } \\)

Explanation:

Step1: Recall the cosine formula

In a right - triangle, \(\cos\theta=\frac{\text{adjacent}}{\text{hypotenuse}}\)

Step2: Identify the sides relative to angle \(B\)

For angle \(B\), the adjacent side is \(64\) and the hypotenuse is \(80\)

Step3: Calculate \(\cos B\)

\(\cos B=\frac{64}{80}\)

Answer:

\(\frac{64}{80}\)