Answer:
Step-by-step explanation:
Our equations are

Let us understand the term Discriminant of a quadratic equation and its properties
Discriminant is denoted by D and its formula is

Where
a= the coefficient of the 
b= the coefficient of 
c = constant term
Properties of D: If D
i) D=0 , One real root
ii) D>0 , Two real roots
iii) D<0 , no real root
Hence in the given quadratic equations , we will find the values of D Discriminant and evaluate our answer accordingly .
Let us start with

Hence we have two real roots for this equation.


Hence we do not have any real root for this quadratic

Hence D>0 and thus we have two real roots for this equation.

Hence we have one real root to this quadratic equation.
The numbers of new CDs is 30 and the old CDs is 21.
To solve this problem, we have to write a system of equations in which we would know the numbers of each types of CD she bought.
<h3>System of Equations</h3>
This is used to solve a series or complex of word problems in which we can represent in a mathematical statements;
- Let n represents numbers of new CDs
- Let u represents numbers of old CDs
The equations can be represented as

Let's take equation (i)
Making n the subject of formula

we can put equation (iii) into equation (ii)

Let's put the value of u into equation (i)

From the calculations above, the numbers of new CDs is 30 and the old CDs is 21.
Learn more on system of equations here;
brainly.com/question/13729904
Answer is highlighted in brown. Hope this helps.
Answer:
OPTION C: 60%
Step-by-step explanation:
Chances of raining the next day + Chances that it will not rain = 100%
One of them should definitely be true.
So, if the chance of it raining tomorrow is 40% then there is 60% chance that it will not rain tomorrow.
This can also seen as follows:
Probability of rain tomorrow + Probability of no rain = 1
Given Probability of rain tomorrow = 40% = 
Probability of no rain tomorrow = 1 - Probability of rain tomorrow
⇒ Probability of no rain = 1 - 
⇒ Probability of no rain = 
Expressing it as percentage:
= 60%.
Hi there!
a. Find the displacement by plugging in the values of the interval:
f(2) - f(0) = 0 - 2 = -2 meters.
Average velocity is the slope, thus:

The average velocity for the interval is -1 m/s.
b. To find the speed at the endpoints, we must take the derivative to get the velocity equation:
f(t) = t² - 3t +2
f'(t) = 2t - 3, at t = 0, speed = |-3| = 3 m/s. At t = 2, speed = 2(2) - 3 = 1 m/s.
Acceleration is the second derivative, thus:
f''(t) = 2. The acceleration is 2 m/s² for both endpoints.
c. When the body changes direction, the first derivative changes signs. Thus:
0 = 2t - 3
3 = 2t, t = 1.5 sec. This is where the body changes direction.