So, when we're tasked with things like this, rewriting everything in terms of sine and cosine and combining fractions often trivializes things, so doing just that gives us:
So out expression is 1/cos(x).
The keyword is "sum" which tells you x, y, and z are being added. One half of the sum means that the sum of the three numbers is going to be divided by 2.
x + y + z
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2
Height would be 21 inches, depth would be 5.
<h3>
Answer: 3. Postulate</h3>
A postulate is something that is assumed to be true and there isn't a proof for it as its something foundational to help set up further proofs later down the road. Another example of a postulate is that a line is defined by two distinct points.
5 2/3 divided by 2 2/3 = 17/3 divided by 8/3 = 17/8 = 2 1/8 miles per hour
2 2/3 divided by 5 2/3 = 8/3 divided by 17/3 = 8/17 hours per mile