Answer:
12
Step-by-step explanation:
let x be the number of men
4:7 = x:21
4/7 = x/21
7x = 84
x = 12
Answer:
f
Step-by-step explanation:
Step-by-step explanation:
3x=-13+1
3x = - 12
x = -12/3
x= -4
Answer:
Step-by-step explanation:
Any point on a given parabola is equidistant from focus and directrix.
Given:
Focus of the parabola is at 
.
Directrix of the parabola is 
.
Let 
be any point on the parabola. Then, from the definition of a parabola,
Distance of from focus = Distance of from directrix.
Therefore,
Squaring both sides, we get
![(x-2)^{2}+(y-8)^{2}=(y-10)^{2}\\(x-2)^{2}=(y-10)^{2}-(y-8)^{2}\\(x-2)^{2}=(y-10+y-8)(y-10-(y-8))...............[\because a^{2}-b^{2}=(a+b)(a-b)]\\(x-2)^{2}=(2y-18)(y-10-y+8)\\(x-2)^{2}=2(y-9)(-2)\\(x-2)^{2}=-4(y-9)\\y-9=-\frac{1}{4}(x-2)^{2}\\y=-\frac{1}{4}(x-2)^{2}+9](https://tex.z-dn.net/?f=%28x-2%29%5E%7B2%7D%2B%28y-8%29%5E%7B2%7D%3D%28y-10%29%5E%7B2%7D%5C%5C%28x-2%29%5E%7B2%7D%3D%28y-10%29%5E%7B2%7D-%28y-8%29%5E%7B2%7D%5C%5C%28x-2%29%5E%7B2%7D%3D%28y-10%2By-8%29%28y-10-%28y-8%29%29...............%5B%5Cbecause%20a%5E%7B2%7D-b%5E%7B2%7D%3D%28a%2Bb%29%28a-b%29%5D%5C%5C%28x-2%29%5E%7B2%7D%3D%282y-18%29%28y-10-y%2B8%29%5C%5C%28x-2%29%5E%7B2%7D%3D2%28y-9%29%28-2%29%5C%5C%28x-2%29%5E%7B2%7D%3D-4%28y-9%29%5C%5Cy-9%3D-%5Cfrac%7B1%7D%7B4%7D%28x-2%29%5E%7B2%7D%5C%5Cy%3D-%5Cfrac%7B1%7D%7B4%7D%28x-2%29%5E%7B2%7D%2B9)
Hence, the equation of the parabola is .
Answer:
. In conclusion, people have to become aware of the dangerous impact fossil fuels have on a long term, and how important it is to shift slowiy to renewable energy resources. However, since the use of renewable energy is a rather new development, it carries the weight of critics and careful long term observation. COuntries have to show commitment to renewable energy and have to evaluate which energy resources are cost-effective and the best with regards to their circumstances The only hindrance of using more renewable energy resources in future could be the finances to install these technologles.
