Question

Which equation can be used to solve for c?

Answer 1

`c=(5)/(cos(35^(\circ)))`

Explanation:

Take a look to the picture I attached you. Now the functions on a right triangle are defined as:

`sin(\theta)=(opposite)/(hypotenuse)\hspace{10}csc(\theta)=(hypotenuse)/(opposite) \\\\cos(\theta)=(adjacent)/(hypotenuse)\hspace{10}sec(\theta)=(hypotenuse)/(adjacent) \\\\tan(\theta)=(opposite)/(adjacent)\hspace{17}cot(\theta)=(adjacent)/(opposite)`

Using the picture and the previous equations, it's easier to conclude that the best trigonometry function to use in this case is the cosine function, therefore:

`cos(35^(\circ))=(5)/(c)`

Finally, solving for c:

`c=(5)/(cos(35^(\circ)))`