Answer:
Im pretty sure the answer is b using the formula
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The probability of at least three heads can be found by<span><span>∑<span>k=3</span>4</span><span>(<span>4k</span>)</span><span>.5k</span><span>.5<span>4−k</span></span>=<span>516</span></span></span>
Answer:
a = 2, b = -9, c = 3
Step-by-step explanation:
Replacing x, y values of the points in the equation y = a*x^2 + b*x +c give the following:
(-1,14)
14 = a*(-1)^2 + b*(-1) + c
(2,-7)
-7 = a*2^2 + b*2 + c
(5, 8)
8 = a*5^2 + b*5 + c
Rearranging:
a - b + c = 14
4*a + 2*b + c = -7
25*a + 5*b + c = 8
This is a linear system of equations with 3 equations and 3 unknows. In matrix notation the system is A*x = b whith:
A =
1 -1 1
4 2 1
25 5 1
x =
a
b
c
b =
14
-7
8
Solving A*x = b gives x = Inv(A)*b, where Inv(A) is the inverse matrix of A. From calculation software (I used Excel) you get:
inv(A) =
0.055555556 -0.111111111 0.055555556
-0.388888889 0.444444444 -0.055555556
0.555555556 0.555555556 -0.111111111
inv(A)*b
2
-9
3
So, a = 2, b = -9, c = 3
The paper for each of them
paper per person = 147/3
paper per person = 49
Each of them deliver 49 papers
Find how long it takes
one paper is 2 minutes
time = 49 × 2
time = 98
They finish delivering in 98 minutes
Answer:
the coefficient of x is 1
Step-by-step explanation:
In the expression ax²+bx+c=0
a is the coefficient of x²
b is the coefficient of x
2+x²+x = x²+x +2 = 1x²+1x +2 =
So in this expression right above the coefficient of x is 1