15. [4] insufficient information. only given SA
16. There are 3 right triangles, 3 Pythagorean theorem equations
x²+b²= 16²
12²+a² = x²
a²+4² = b²
combine equations using substitution to get in terms of only x
substitute b² for (a² +x²) in first equation
x²+a²+4²=16²
substitute a² for (x² - 12²)
x²+x²-12²+4² = 16²
solve for x
2x² - 144 + 16 = 256
2x² = 256 + 144 - 16
2x² = 384
x² = 384/2
x² = 192
x = 13.85
rounded to nearest tenth, x = 13.9
Using the change in base property, we have
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approximately.
The inequality is a > 12, which means a is greater than 12. This means that we are looking for numbers that are greater than 12 to place into the solution set. Options A and B are incorrect because 10 and 11 are both numbers less than 12, respectively. Option D is also incorrect because the inequality specifies that the numbers in the solution must be greater than 12, not equal to it, so 12 is not a solution.
This leaves option C as the correct answer, because all of the solutions in the set (13, 14, and 15) are greater than 12.
Therefore, your answer is C.
Hope this helps!
Answer:
the one with one line and the one that is parallel, Basically the two on top^_^