La of sine:
sinC/c = sinB/b==> sin 37°/8 = sin B/12 ==> sin B = 0.903
arcsinB or sin⁻¹ B = 64.5°, & sin (B°) = sin (180° - B°), then
sin(64.5) = sin(180°-64.5°) ==> B = 64.5° or 115.5°
25 miles and 5 miles because you only multiply two sides to find the area 25•5=125
Answer:
1) maldava y despota
2) pequenos
Step-by-step explanation:
Answer:
![\displaystyle \frac{1-x}{(5-x)(-x)} =-\frac{x-1 }{ x(x-5)}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B1-x%7D%7B%285-x%29%28-x%29%7D%20%3D-%5Cfrac%7Bx-1%20%7D%7B%20x%28x-5%29%7D)
![\displaystyle \frac{5}{s}\times \frac{2}{5} =\frac{2}{s}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B5%7D%7Bs%7D%5Ctimes%20%5Cfrac%7B2%7D%7B5%7D%20%3D%5Cfrac%7B2%7D%7Bs%7D)
Step-by-step explanation:
<u>Errors in Algebraic Operations
</u>
It's usual that students make mistakes when misunderstanding the application of algebra's basic rules. Here we have two of them
- When we change the signs of all the terms of a polynomial, the expression must be preceded by a negative sign
- When multiplying negative and positive quantities, if the number of negatives is odd, the result is negative. If the number of negatives is even, the result is positive.
- Not to confuse product of fractions with the sum of fractions. Rules are quite different
The first expression is
![1-x / (5-x)(-x)=x-1 / x(x-5)](https://tex.z-dn.net/?f=1-x%20%2F%20%285-x%29%28-x%29%3Dx-1%20%2F%20x%28x-5%29)
Let's arrange into format:
![\displaystyle \frac{1-x}{(5-x)(-x)} =\frac{x-1 }{ x(x-5)}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B1-x%7D%7B%285-x%29%28-x%29%7D%20%3D%5Cfrac%7Bx-1%20%7D%7B%20x%28x-5%29%7D)
We can clearly see in all of the factors in the expression the signs were changed correctly, but the result should have been preceeded with a negative sign, because it makes 3 (odd number) negatives, resulting in a negative expression. The correct form is
![\displaystyle \frac{1-x}{(5-x)(-x)} =-\frac{x-1 }{ x(x-5)}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B1-x%7D%7B%285-x%29%28-x%29%7D%20%3D-%5Cfrac%7Bx-1%20%7D%7B%20x%28x-5%29%7D)
Now for the second expression
![5/s+2/5=2/s](https://tex.z-dn.net/?f=5%2Fs%2B2%2F5%3D2%2Fs)
Let's arrange into format
![\displaystyle \frac{5}{s}+\frac{2}{5} =\frac{2}{s}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B5%7D%7Bs%7D%2B%5Cfrac%7B2%7D%7B5%7D%20%3D%5Cfrac%7B2%7D%7Bs%7D)
It's a clear mistake because it was asssumed a product of fractions instead of a SUM of fractions. If the result was correct, then the expression should have been
![\displaystyle \frac{5}{s}\times \frac{2}{5} =\frac{2}{s}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B5%7D%7Bs%7D%5Ctimes%20%5Cfrac%7B2%7D%7B5%7D%20%3D%5Cfrac%7B2%7D%7Bs%7D)