Huh? What do you mean I don't understand
Answer:
Step-by-step explanation:
4x+2y = -24 -------------(i)
<u> -4x+y = 12 -</u>------------(ii)
add (i) &(ii) 3y = -12
y = -12/3
y = -4
Put y = (-4) in (i)
4x + 2*(-4) = -24
4x - 8 = -24
4x = -24 + 8
4x = -16
x = -16/4
x = -4
Just for future reference always put ^ for exponents. The answer is y-6 though.
(y-4)(y-6) create that trinomial. You can prove that by using the FOIL algorithm
Sum of the first two is:
-3x+5+7-4x = -7x+12
That subtracted from 5x+17:
5x+17-(-7x+12) = 12x+5
Answer:
Mean = 35
Variance = 291.7
Step-by-step explanation:
Data provided in the question:
X : 1, 2, 3, 4, 5, 6
All the data are independent
Thus,
The mean for this case will be given as:
Mean, E[X] = 
or
E[X] = 
or
E[X] = 3.5
For 10 days, Mean = 3.5 × 10 = 35
And,
variance = E[X²] - ( E[X] )²
Now, for this case of independent value,
E[X²] = 
or
E[X²] = 
or
E[X²] = 
or
E[X²] = 15.167
Therefore,
variance = E[X²] - ( E[X] )²
or
variance = 15.167 - 3.5²
or
Variance = 2.917
For 10 days = Variance × Days²
= 2.917 × 10²
= 291.7