Answer:
The cosine of A is equal to [tex]\frac{3\sqrt{58}}{58}\\[/tex]
Step-by-step explanation:
Cosine is is calculated as adjacent over hypotenuse. The line adjacent to A is 3 in length.
So we can say that the cosine is equal to 3/√58, but need to multiply it by √58 / √58 to ensure we have a non-radical denominator
[tex]A = \frac{3}{\sqrt{58}}\\A = \frac{3\sqrt{58}}{58}\\[/tex]
