Looks to Be answer A have a great day!
Expressions equivalent can be:
-2(5c)
-2*-5c
=10c
You turn 2/3 into 6/9
Then turn 1 4/9 into an improper fraction 13/9
Then subtract and you get 7/9
The answer is 7/9
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Answer:

Step-by-step explanation:
sec(theta) is defined as: 
In the diagram you provided the hypotenuse of the triangle is sqrt(41) and the opposite side is 5, using these two sides, we can solve for the adjacent side by using the Pythagorean Theorem: 
So this gives us the equation where a=adjacent side:

Subtract 25 from both sides

Take the square root of both sides

So now plug this into the definition of sec(theta) and you get:
. This is in most simplified form since 41, has no factors besides 41 and 1.