Suppose ABC Is a Right Triangle with Sides of Length $\cos \mathrm { A }$

question 77

Multiple Choice

Suppose ABC is a right triangle with sides of length a, b, and c and right angle at C. Find the exact value of the indicated
trigonometric function. You may need to use the Pythagorean theorem to find the unknown side length. Rationalize the
denominator if necessary.
-Find $\cos \mathrm { A }$ when $a = 2$ and $b = 7$ .

• A) \(\frac { 7 \sqrt { 53 } } { 53 }\)
• B) \(\frac { \sqrt { 53 } } { 2 }\)
• C) \(\frac { 2 \sqrt { 53 } } { 53 }\)
• D) \(\frac { \sqrt { 53 } } { 7 }\)

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Definitions:

Productive

Relating to or involving the creation of goods or services that satisfy human wants; the efficiency and effectiveness in producing outputs from inputs.

Constant Returns To Scale

A condition where increasing all inputs by any proportion results in output increasing by that same proportion, indicating that size does not affect productivity.

Long-Run Average Total Cost

The cost per unit of output incurred when all factors of production are variable, and scale of production can be changed.

Output

The amount of products or services produced by a company, industry, or economic system.