So first create and define your variables:
Z = amount of zebra fish
N = amount of neon tetras
Now create your equations:
2z+2.15n=31.20
z+n=15
This is your system. There are multiple methods to use but in this problem I’ll use the substitution method by simplifying the bottom equation.
2z+2.15n=31.20
z=15-n
Now I’ll plug the bottom equation into the top one.
2(15-n)+2.15n=31.20
And just solve from here.
30-2n+2.15n=31.20
0.15n=1.20
n=8
So he bout 8 neon tetras, and 15-8= 7, so he bought 7 zebra fish
-2a from both sides then divide by -5 and a=1
Answer:
The probability of getting two of the same color is 61/121 or about 50.41%.
Step-by-step explanation:
The bag is filled with five blue marbles and six red marbles.
And we want to find the probability of getting two of the same color.
If we're getting two of the same color, this means that we are either getting Red - Red or Blue - Blue.
In other words, we can find the independent probability of each case and add the probabilities together*.
The probability of getting a red marble first is:
![\displaystyle P\left(\text{Red}\right)=\frac{6}{11}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%5Cleft%28%5Ctext%7BRed%7D%5Cright%29%3D%5Cfrac%7B6%7D%7B11%7D)
Since the marble is replaced, the probability of getting another red is: ![\displaystyle P\left(\text{Red, Red}\right)=\frac{6}{11}\cdot \frac{6}{11}=\frac{36}{121}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%5Cleft%28%5Ctext%7BRed%2C%20Red%7D%5Cright%29%3D%5Cfrac%7B6%7D%7B11%7D%5Ccdot%20%5Cfrac%7B6%7D%7B11%7D%3D%5Cfrac%7B36%7D%7B121%7D)
The probability of getting a blue marble first is:
![\displaystyle P\left(\text{Blue}\right)=\frac{5}{11}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%5Cleft%28%5Ctext%7BBlue%7D%5Cright%29%3D%5Cfrac%7B5%7D%7B11%7D)
And the probability of getting another blue is:
![\displaystyle P\left(\text{Blue, Blue}\right)=\frac{5}{11}\cdot \frac{5}{11}=\frac{25}{121}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%5Cleft%28%5Ctext%7BBlue%2C%20Blue%7D%5Cright%29%3D%5Cfrac%7B5%7D%7B11%7D%5Ccdot%20%5Cfrac%7B5%7D%7B11%7D%3D%5Cfrac%7B25%7D%7B121%7D)
So, the probability of getting two of the same color is:
![\displaystyle P(\text{Same})=\frac{36}{121}+\frac{25}{121}=\frac{61}{121}\approx50.41\%](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%28%5Ctext%7BSame%7D%29%3D%5Cfrac%7B36%7D%7B121%7D%2B%5Cfrac%7B25%7D%7B121%7D%3D%5Cfrac%7B61%7D%7B121%7D%5Capprox50.41%5C%25)
*Note:
We can only add the probabilities together because the event is mutually exclusive. That is, a red marble is a red marble and a blue marble is a blue marble: a marble cannot be both red and blue simultaneously.
First you will use the slope formula:
M= Rise/Run = Y2-Y1/X2-X1
(0,13) (-4,10)
10-13
——— = -3/4 = 3/4
-4-0.
Answer:
x+5 (under assumption you meant to do -3x
Step-by-step explanation:
you can use long division.
Take the leading coefficient x^4 and divide it by x^3. This results in x which is going to be the first part of you quotient. Now take that x and multiply it by the divisor (x^3 - 3). This gives you x(x^3 - 3) = x^4 - 3x. Now subtract that x^4 - 3x from the original polynomial and repeat this until you can't divide anymore
![x^4+5x^3-3x-15 - (x^4-3x) = 5x^3-15\\x^3/5x^3=5\\5(x^3-3) = 5x^3-15\\5x^3-15-(5x^3-15) = 0\\\\x+5](https://tex.z-dn.net/?f=x%5E4%2B5x%5E3-3x-15%20-%20%28x%5E4-3x%29%20%3D%205x%5E3-15%5C%5Cx%5E3%2F5x%5E3%3D5%5C%5C5%28x%5E3-3%29%20%3D%205x%5E3-15%5C%5C5x%5E3-15-%285x%5E3-15%29%20%3D%200%5C%5C%5C%5Cx%2B5)