Answer:
A
Step-by-step explanation:
Let's label what we currently have:
[tex]Hypotenuse = x[/tex]
[tex]Opposite = 12[/tex]
[tex]Adjacent = ?[/tex]
Since the answer choices are asking us to use cosine, we will need to use the cosine formula:
[tex]cos=\frac{adjacent}{hypotenuse}[/tex]
It seems like we don't have the adjacent side yet. However, if we use another angle, we can find out what x is. We know one angle is 35°. Since it is a right triangle, the other angle is 90°. Since all triangles add up to 180°, we know that the other angle is 55°. We CAN use cosine to find x if we use the 55° angle.
Let's label our new areas:
[tex]Hypotenuse=x[/tex]
[tex]Opposite=?[/tex]
[tex]Adjacent=12[/tex]
By using the cosine formula, we can now use the two values we have in the equation.
[tex]cos 55=\frac{12}{x}[/tex]
