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
Let's assume the frequency of sound be f and wave length is w.
Given that, the frequency of sound varies inversely as the wavelength.
So, we can set up an equation as following:
f*w = k Where k= constant of variation.
Other information is, the frequency of a musical note is 276 cycles per second when the wavelength is 1.2m.
So, next step is to plug in f = 276 and w = 1.2 in the above equation to get the value of k.
276 * 1.2 = k
So, k = 331.2
Next step is to plug in k = 331.2 in the above equation. So,
f * w = 331.2
Now we need to find the wave length : w when frequency : f = 600.
Therefore,
600 * w = 331.2

So, w = 0.552
Hence, the wave length is 0.552 m.
Hope this helps you!.
Answer:
Step-by-step explanation:
(2n - 3)(5n + 6) = 2n*(5n + 6) -3*(5n +6)
=2n*5n + 2n*6 -3*5n + (-3)*6
=10n² + 12n - 15n - 18
= 10n² -3n - 18
Answer:

Step-by-step explanation:
it's so simple dude