Sometimes because it might not always be true
Answer:
The number is -32
Step-by-step explanation:
Let the number be x, then 11 minus the quotient of a number and 8 is 15 becomes:
![11 - \frac{x}{8} = 15](https://tex.z-dn.net/?f=11%20-%20%20%5Cfrac%7Bx%7D%7B8%7D%20%20%3D%2015)
We group similar terms to get:
![- \frac{x}{8} = 15 - 11](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7Bx%7D%7B8%7D%20%20%3D%2015%20-%2011)
![- \frac{x}{8} = 4](https://tex.z-dn.net/?f=-%20%20%5Cfrac%7Bx%7D%7B8%7D%20%20%3D%204)
Multiply both sides by -8 to get:
![x = 4 \times - 8](https://tex.z-dn.net/?f=x%20%3D%204%20%5Ctimes%20%20-%208)
Simplify to get:
![x = - 32](https://tex.z-dn.net/?f=x%20%3D%20%20-%2032)
Answer:
∠EFC and ∠DCF
∠BCF and ∠GFC
Step-by-step explanation:
Answer: Okay...what's your question?
Step-by-step explanation:
This is actually a lot easier than it seems :-)! There is a formula in trig called the Pythagorean Theorem. This is cos^2 x + sin^2 x = 1. This means that cos^2 x means the exact same thing as 1-sin^2 x. If we plug this in, we get 1-2sin^2 pi/9. Another helpful trigonometric equation is the double angle identity. This is cos(2x)=1-2sin^2 (x). Plugging our equation from earlier in, we get cos 2pi/9.