I'm not sure why options a. and d. are the same, but you would simply count the number of times x and m appear, while being multiplied together, and multiply the product of xm by that number. in this case, the number is 7, so you should get 7(xm) or 7xm.
Answer:
The events must be independent.
Step-by-step explanation:
The only assumption that must be made is that the events are independent. That is, the amount of soda in a given can does not depend on the amount of soda of any previous can filled at the same facility.
If this assumption holds, then the probability of finding exactly k cans of soda filled correctly would be
where
are combinations of 100 elements taken k at a time.
Let the first brother = x
second brother = x + 2
third brother = x + 4
<span>The product of the first and third boys' ages is 20 more than twice the second boy's age:
x(x+4) = 2(x+2) + 20
x</span>² + 4x = 2x + 4 + 20
x² + 4x - 2x - 24 = 0
x² + 2x - 24 = 0
(x - 4)(x + 6) = 0
x = 4 or -6 (rejected, age cannot be negative)
First brother = 4
Second brother = 4 + 2 = 6
Third brother = 4 + 4 = 8
The three boys are 4, 6, and 8 years old.
Answer:
two real roots
Step-by-step explanation:
y = -2x^2 + 9x - 7
This is in the form
ax^2 +bx+c
a = -2 b = 9 c = -7
The discriminant is
b^2 -4ac
(9)^2 - 4(-2) (-7)
81 - 56
25
Since the discriminant is greater than zero, there are two real roots
