Answer:
Not independent
Step-by-step explanation:
Given that in a certain population of married couples, 30% of the husbands smoke, 20% of the wives smoke, and in 8% of the couples both the husband and the wife smoke.
Let A be the event that husbands smoke and B the event that wives smoke
Give that
To check whether A and B are independent it is sufficient to check
P(A\bigcap B)=P(A)P(B)
Right side=
Left side = 0.08
Since two sides do not equal the two events are not independent.
Answer:
set middle number=x
then left side number=x-1
and right side number=x+1
(x-1)+x+(x+1)＝30
3x=30
x=10
x-1=9
x+1=11
numbers are 9,10,11
<u>Answer</u>
y⁻¹ = ∛(4x+8)
<u>Explanation</u>
y=(1/4)x³ - 2.
To find the inverse of this equation, you first make x the subject of the formular.
y=(1/4)x³ - 2
Multiply both sides by 4;
4y = x³ - 8
Add 8 on both sides of the equation;
4y + 8 = x³
x³ = 4y + 8
Apply the cube root on both sides to get the value of x;
x = ∛(4y+8)
The inverse of y=(1/4)x³ - 2 is;
y⁻¹ = ∛(4x+8)
These are two questions and two answers:
Question 1:
<span>A
quadratic equation is shown below: 3x^2 − 15x + 20 = 0 Part A: Describe
the solution(s) to the equation by just determining the radicand. Show
your work.
Answer: </span><span>The negative value of the radicand means that the equation does not have real solutions.
Explanation:
1) With radicand the statement means the disciminant of the quadratic function.
2) The discriminant is: b² - 4ac, where a, b, and c are the coefficients of the quadratic equation: ax² + bx + c
3) Then, for 3x² - 15x + 20, a = 3, b = - 15, and c = 20
and the discriminant (radicand) is: (-15)² - 4(3)(20) = 225 - 240 = - 15.
4) The negative value of the radicand means that the equation does not have real solutions.
Question 2:
Part B: Solve 3x^2 + 5x − 8 = 0 by using an appropriate
method. Show the steps of your work, and explain why you chose the
method used.
Answer: </span> two solutions x = 1 and x = - 8/3x
Explanation:
1) I choose factoring (you may use the quadratic formula if you prefer)
2) Factoring
Given: 3x² + 5x − 8 = 0
Make 5x = 8x - 3x: 3x² + 8x - 3x - 8 = 0
Group: (3x² - 3x) + (8x - 8) = 0
Common factors for each group: 3x(x -1) + 8(x - 1) = 0
Coomon factor x - 1: (x - 1) (3x + 8) = 0
The two solutions are for each factor equal to zero:
x - 1 = 0 ⇒ x = 1
3x + 8 = 0 ⇒ x = -8/3
Those are the two solutions. x = 1 and x = - 8/3
A. x intercept is -8 ; y intercept is 4
