The Venn Diagram that represents the problem is shown below
P(E|F) and P(F|E) are the conditional probability.
P(E|F) is given by P(E∩F) ÷ P(F) = ¹/₂ ÷ ¹/₂ = 1
P(F|E) is given by P(F∩E) ÷ P(E) = ¹/₂ ÷ ¹/₂ = 1
To solve the quadratic equation given by 0=x^2-9x-20, we use the quadratic formula given by:
x=[-b+\- sqrt(b^2-4ac)]/(2a)
where,
a=1,b=-9,c=-20
thus substituting the above values into our formula we get:
x=[9+\-sqrt(9^2-4(-20*1))/(2*1)
x=[9+\-sqrt(161)]/2
x=[9+sqrt161]/2 or x=[9-sqrt161]/2
Answer: 2000
Step-by-step explanation:
55 multiplied by 20
is equal to 1,100
100 multiplied by 20
is equal to 2000
2000 ppl were surveyed
So let's say quarters = x and dimes = y. You'd then put x + y = 77 (for a total of 77 coins). And your second equation would be .25x + .10y = 12.50 (.25 for the total value a quarter holds and .10 for a total value a dime holds). Then you'd do matrices on a calculator.