80 because of you cross multiply 6 times x and 30 times 16 you get 480 and 6 divided by 480 is 80
6/16=30/?
6x=480
Divided by 6
?=80
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:
9
Step-by-step explanation:
a²+b
Substituting values,
=> (-2)^2+5
=> 4 + 5
=> 9
Answer:
C.1/6
Step-by-step explanation:
Initially the box has four $1 and six $5 bills. The probability of selecting a $5 bill in the first trial would be given as;
(number of $5 bills) / (total number of bills)
= (6)/(4+6) = 3/5
If in the first attempt we actually pick a $5 bill, the number of $5 bills will reduce by one to 5. Now, the probability of picking a $5 bill in the second attempt will be given as;
(new number of $5 bills) / (new total number of bills)
= (5)/(4+5) = 5/9
The new number of $5 bills will now be; 6 - 2 = 4 since we have already picked 2 without replacing them.
Now, the probability of picking a $5 bill in the third attempt will be given as;
(new number of $5 bills) / (new total number of bills)
= (4)/(4+4) = 1/2
Since the three attempts are independent, the probability of picking all three $5 bills is;
3/5 * 5/9 * 1/2 = 1/6
