S=2(4x+2x)+4x^2=4x^2+12x
4x^2+12x=7
4x^2+12x-7=0
D=12^2-4x4x(-7)=256
X1=(-12-16)/(2x4)=-3.5 impossible
X2=(-12+16)/(2x4)=0.5
A
D divide by 1000… you are shifting the decimal 3 places (there are 3 zeros in 1000) you are dividing because the number is getting smaller.
Answer:
Step-by-step explanation:
The top triangle is similar to the whole triangle because of AAA
Then we know that the corresponding sides are similar
9/81=(3x-20)/(3x-20+56)
1/9=(3x-20)/(3x+36)
cross multiply
9(3x-20)=3x+36
27x-180=3x+36
24x=216
x=9
Answer:
Step-by-step explanation:
-7-1=-8
if events X and Y are independent, then for intersection we multiply the probability
P(Y∩X) = P(Y) * P(X)
We know that
![P(Y|X) =\frac{P(YintersectionX)}{P(X)}](https://tex.z-dn.net/?f=P%28Y%7CX%29%20%3D%5Cfrac%7BP%28YintersectionX%29%7D%7BP%28X%29%7D)
Now we replace P(Y) * P(X) for P(Y∩X)
![P(Y|X) =\frac{P(Y)*P(X)}{P(X)}](https://tex.z-dn.net/?f=P%28Y%7CX%29%20%3D%5Cfrac%7BP%28Y%29%2AP%28X%29%7D%7BP%28X%29%7D)
Cancel out P(X)
So ![P(Y|X) = P(Y)](https://tex.z-dn.net/?f=P%28Y%7CX%29%20%3D%20P%28Y%29)
Like that
![P(X|Y) =\frac{P(XintersectionY)}{P(Y)}](https://tex.z-dn.net/?f=P%28X%7CY%29%20%3D%5Cfrac%7BP%28XintersectionY%29%7D%7BP%28Y%29%7D)
Now we replace P(X) * P(Y) for P(X∩Y)
![P(X|Y) =\frac{P(X)*P(Y)}{P(Y)}](https://tex.z-dn.net/?f=P%28X%7CY%29%20%3D%5Cfrac%7BP%28X%29%2AP%28Y%29%7D%7BP%28Y%29%7D)
Cancel out P(Y)
So ![P(X|Y) = P(X)](https://tex.z-dn.net/?f=P%28X%7CY%29%20%3D%20P%28X%29)
P(Y | X) = P(Y) and P(X | Y) = P(X) are true