Answer:
-2x^2-20x-46
Step-by-step explanation:
-2(x^2)-20x-46
-2(x^2) -2(10x)-46
-2(x^2)-2(10x)-2(23)
-2(x^2+10x)-2(23)
-2x^2-20x-46
Answer: 15 1/2
Step-by-step explanation: There are two 1/2 s so 1/2 + 1/2 is 2/2 or 1 whole. Next is 1. There are 4 ones. 1+1+1+1 = 4. There is one 1 1/2. There are two 2. 2+2 is 4. There are two 2 1/2 so 2 1/2 + 2 1/2 is 4 2/2 which is 5. Now you have to add all the answers together. 1 +4+ 1 1/2 +4+5 which is 15 and 1/2. 15 1/2 is the answer.
68% +75 % +79 % +x ÷4≥ 80%
.68 + .75 + .79+x ÷4* 4 ≥ . 80*4
.68 + .75 + .79+x ≥ 3.2
2.22 + x ≥ 3.2
2.22 -2.22+x ≥ 3.2 -2.22
x ≥ 0.98
She has to get at least 98% to get an B.
To determine The probability of both of these occurring, you would multiply the probability of each together. So, there is a 1/7 chance of the first salesman getting the right key, and 1/6 chance of the second salesman getting the right key. 1/7 x 1/6= 1/42 chance of both occurring.
Answer:
The statement is true is for any
.
Step-by-step explanation:
First, we check the identity for
:



The statement is true for
.
Then, we have to check that identity is true for
, under the assumption that
is true:
![(1^{2}+2^{2}+3^{2}+...+k^{2}) + [2\cdot (k+1)-1]^{2} = \frac{(k+1)\cdot [2\cdot (k+1)-1]\cdot [2\cdot (k+1)+1]}{3}](https://tex.z-dn.net/?f=%281%5E%7B2%7D%2B2%5E%7B2%7D%2B3%5E%7B2%7D%2B...%2Bk%5E%7B2%7D%29%20%2B%20%5B2%5Ccdot%20%28k%2B1%29-1%5D%5E%7B2%7D%20%3D%20%5Cfrac%7B%28k%2B1%29%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29-1%5D%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29%2B1%5D%7D%7B3%7D)
![\frac{k\cdot (2\cdot k -1)\cdot (2\cdot k +1)}{3} +[2\cdot (k+1)-1]^{2} = \frac{(k+1)\cdot [2\cdot (k+1)-1]\cdot [2\cdot (k+1)+1]}{3}](https://tex.z-dn.net/?f=%5Cfrac%7Bk%5Ccdot%20%282%5Ccdot%20k%20-1%29%5Ccdot%20%282%5Ccdot%20k%20%2B1%29%7D%7B3%7D%20%2B%5B2%5Ccdot%20%28k%2B1%29-1%5D%5E%7B2%7D%20%3D%20%5Cfrac%7B%28k%2B1%29%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29-1%5D%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29%2B1%5D%7D%7B3%7D)
![\frac{k\cdot (2\cdot k -1)\cdot (2\cdot k +1)+3\cdot [2\cdot (k+1)-1]^{2}}{3} = \frac{(k+1)\cdot [2\cdot (k+1)-1]\cdot [2\cdot (k+1)+1]}{3}](https://tex.z-dn.net/?f=%5Cfrac%7Bk%5Ccdot%20%282%5Ccdot%20k%20-1%29%5Ccdot%20%282%5Ccdot%20k%20%2B1%29%2B3%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29-1%5D%5E%7B2%7D%7D%7B3%7D%20%3D%20%5Cfrac%7B%28k%2B1%29%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29-1%5D%5Ccdot%20%5B2%5Ccdot%20%28k%2B1%29%2B1%5D%7D%7B3%7D)

![(2\cdot k +1)\cdot [k\cdot (2\cdot k -1)+3\cdot (2\cdot k +1)] = (k+1) \cdot (2\cdot k +1)\cdot (2\cdot k +3)](https://tex.z-dn.net/?f=%282%5Ccdot%20k%20%2B1%29%5Ccdot%20%5Bk%5Ccdot%20%282%5Ccdot%20k%20-1%29%2B3%5Ccdot%20%282%5Ccdot%20k%20%2B1%29%5D%20%3D%20%28k%2B1%29%20%5Ccdot%20%282%5Ccdot%20k%20%2B1%29%5Ccdot%20%282%5Ccdot%20k%20%2B3%29)



Therefore, the statement is true for any
.