Answer:
a = 0.25
Step-by-step explanation:
Our strategy to solve this problem will be to use the information given in the table to obtain first the value of c in the quadratic equation which has the form ax^2 + bx + c and then form a system of 2 linear equations and solve for the coefficients a and b as follow:
from x=0 and y=-3 a*0 + b* 0 + c = - 3
c = -3
from x=1 and y= -3.75
a*(1) + *(1) + (-3) = -3.75
a + b = -3.75 + 3 = -0.75
from x= 2 and y = -4
a* (2)^2 + b*(2) + (-3) = -4
4a + 2b = -4 +1
4a + 2b = -1
Now we can solve the system f equations by elimination:
a + b = -0.75
4a + 2b = -1
multiply first equation by -2 and add to the second and get
-2a - 2b = +1.50
4a + 2b = -1
2a = 0.50 and substituting into any of the equations get b = -1
so the quadratic equation has a= 0.25 b= -1 c= -3
we can even plug the any of the other values for x given in the table and check the answer.
Answer:
a) x-4+9
b) x-2
For part b, I am not 100% sure about my answer, but I am sure about part a.
It would be 2 O'clock. Have a great day!!
2 possibilities for each person, for 8 people
= 2*2*2*2*2*2*2*2
=2^8
= 256 ways of announcing the result
