Respuesta :

Answer: 0.8

Step-by-step explanation:

Using the Cosine formula :

[tex]Cos A = \frac{b^{2}+c^{2}-a^{2}}{2bc}[/tex]

[tex]a = 6[/tex]

[tex]b = 8[/tex]

[tex]c = 10[/tex]

substituting into the formula , we have

[tex]Cos A = \frac{8^{2}+10^{2}-6^{2}}{2(8)(10)}[/tex]

[tex]Cos A = \frac{64+100-36}{160}[/tex]

[tex]Cos A = \frac{164-36}{160}[/tex]

[tex]Cos A = \frac{128}{160}[/tex]

Therefore :

Cosine of angle A = 0.8