?????? help pls lolll

Solving quadratic equations with complex solutions x2 + 4x + 8 = 0.

Daniel [21]

Answer:

$\large\boxed{x=-2\pm2i}$

Step-by-step explanation:

$x^2+4x+8=0\qquad\text{subtract 8 from both sides}\\\\x^2+4x+8-8=0-8\\\\x^2+2(x)(2)=-8\qquad\text{add}\ 2^2\ \text{to both sides}\\\\x^2+2(x)(2)+2^2=-8+2^2\qquad\text{use}\ (a+b)^2=a^2+2ab+b^2\\\\(x+2)^2=-8+4\\\\(x+2)^2=-4\iff x+2=\pm\sqrt{-4}\\\\x+2=\pm\sqrt{(4)(-1)}\qquad\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\x+2=\pm\sqrt4\cdot\sqrt{-1}\qquad\text{use}\ \sqrt{-1}=i\\\\x+2=\pm2\cdot i\qquad\text{subtract 2 from both sides}\\\\x=-2\pm2i$

4 0

3 years ago

Statistics Probability

andriy [413]

Answer:

Explained below.

Step-by-step explanation:

Denote the variable as follows:

M = male student

F = female student

Y = ate breakfast

N = did not ate breakfast

(a)

Compute the probability that a randomly selected student ate breakfast as follows:

$P(Y)=\frac{n(Y)}{N}\\\\=\frac{198}{330}\\\\=0.60$

(b)

Compute the probability that a randomly selected student is female and ate breakfast as follows:

$P(F\cap Y)=\frac{n(F\cap Y)}{N}\\\\=\frac{121}{330}\\\\=0.367$

(c)

Compute the probability a randomly selected student is male, given that the student ate breakfast as follows:

$P(M|Y)=\frac{n(M\cap Y)}{n(Y)}\\\\=\frac{77}{198}\\\\=0.389$

(d)

Compute the probability that a randomly selected student ate breakfast, given that the student is male as follows:

$P(Y|M)=\frac{n(Y\cap M)}{n(M)}\\\\=\frac{77}{154}\\\\=0.50$

(e)

Compute probability of the student selected "is male" or "did not eat breakfast" as follows:

$P(M\cup N)=P(M)+P(N)-P(M\cap N)\\\\=\frac{n(M)}{N}+\frac{n(N)}{N}-\frac{n(M\cap N)}{N}\\\\=\frac{n(M)-n(N)-n(M\cap N)}{N}\\\\=\frac{154+132-77}{330}\\\\=0.633$

(f)

Compute the probability of "is male and did not eat breakfast as follows:

$P(M\cap N)=\frac{n(M\cap N)}{N}\\\\=\frac{77}{330}\\\\=0.233$

4 0

3 years ago

Please tell the answer and show the work.

LUCKY_DIMON [66]

First step, i would try to figure out the slope. think of it as a typical y=mx+b linear equation as you check out the graph.

it's just rise over run (rise up this many, run over that many), and your options are (-2/3) or (-3/2)

start at the y-intercept, which is just above the middle of the graph. if you go down 2 and try to go over 3, you hit the line before you can count 3 units. that means this slope is incorrect.

go back to the y-intercept. down 3, over 2--there you go. your slope here is (-3/2), which immediately gets rid of half your answer choices for having the wrong slope

the next thing you have to do is decide <em>where</em> this graph should be shaded. the shaded region shows the domain; the white region shows what's outside of your domain. this inequality is shaded "below" which means that the y values are LESS than "(-3/2)x +1"

that eliminates another one of your answer choices; choice 3 is correct. the inequality is y < (-3/2)x + 1

if the graphs of inequalities are shaded below and the line is dotted, it's less than. if the graphs of inequalities are shaded above and the line is dotted, it's greater than. general rules for ya

5 0

3 years ago

Read 2 more answers

Explain the difference between an equation and an inequality. Write at least two of each, one of the form px+q and one of the fo

Triss [41]

Answer: One important difference between an equation and an inequality is that if you subtract one side of an equation from the other, you will get 0

In the case of an inequality, if you subtract one side from the other, you will get something other than 0

That’s an important fact about equations and inequalities that is often utilized in finding solutions.

When I was teaching I noticed that students frequently interpreted the =

sign to mean ‘find the answer’. It does not mean that. It only means that the expression on the left hand side has the same value as the expression on the right hand side.

Students who think that =

means ‘find the answer’ become confused when they see symbols like < , ≠

, or ≈

A further issue these days has to do with computational technology.

This issue has to do with variable assignment. In many programming languages, a statement like =+1x1

has the meaning, “Add one to the current value of x

and then reassign that value to x

.” However, the equation =+1x1

has no solution in traditional algebra.

Programming languages that use =

for variable assignment tend to use ==

to mean equality in our traditional math sense.

Though something like the meaning of =

might seem trivial and ‘obvious’ to many people, there’s actually a lot of subtle variations of understanding possible, and it is important to be aware of these nuances, because that is where confusions arise for students.

7 0

2 years ago

Combine like terms to write the expression in simplest form.<br> 42? + 5y? 2² - 3y²<br> 3y” — Бу

rosijanka [135]

Answer:Missing: 3y² ‎Бу

Step-by-step explanation:

6 0

2 years ago

Read 2 more answers

?????? help pls lolll​

?????? help pls lolll