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3 years ago

Which of the following is a solution of x2 + 2x + 4?

Mathematics

1 answer:

kifflom [539]3 years ago

4 0

Answer:

−1 + i times the square root of 3

is the answer.

Step-by-step explanation:

Given is a quadratic equation in x

$x^2+2x+4\\= x^2+2x+1+3\\=(x+1)^2+3$

using completion of squares method

Equate to 0

$(x+1)^2+3 =0\\(x+1)^2 = -3\\$

Take square root

$(x+1) = \sqrt{-3} =±i\sqrt{3}$

Subtract one from both sides

x = [/tex]-1±i\sqrt{3}[/tex]

The last option namely

−1 + i times the square root of 3 only matches with our answre

Hence last option is right.

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At a drive through restaurant Juan’s family ordered a small drink and m medium drinks. Alex’s family ordered m medium drinks and

sertanlavr [38]

Answer:

Expression x + 2my + z represents cost of order where x, y, z are cost of small , medium and large drinks (in dollars) respectively.

Solution:

Given that

Juan’s family ordered a small drink and m medium drinks.

Alex family ordered m medium drinks and a large drink.

Need to write an algebraic expression which shows total cost of both order in dollars.

Let’s assume cost of one small drink = x

And assume cost of one medium drink = y

And assume cost of one large drink = z

So now cost of order of Juan’s family is equal to cost of 1 small drink + cost of m medium drinks = 1 $\times$ x + m $\times$ y

= x + my

And cost of order of Alex family is equal to cost of m medium drinks + cost of one large drink

= m x y + 1 x z

=my + z

So total cost of both order in dollars = x + my + my + z = x + 2my + z

Hence expression x + 2my + z represents cost of order where x , y , z are cost of small , medium and large drinks (in dollars) respectively.

5 0

3 years ago

Which of the following identfies andrew solomans main claim in the speech

Rama09 [41]

Answer:

What are the following

Step-by-step explanation:

you didn't attach anything for us to answer

7 0

3 years ago

The Math Counts Club had a party at their school. There were 20 cookies and 40 slices of pizza to be shared equally. Each studen

pychu [463]

Answer:

2, 4, 10 or 20 students

Step-by-step explanation:

Prime factors:

20 = 2*2*5
40 = 2*2*2*5

Common factors of the two numbers:

2, 4, 10, 20

Possible number of students as above

4 0

3 years ago

8.46 If 100 is decreased by a% and the result is decreased by b%, then what is the total percent decrease (in terms of a and b)?

Marysya12 [62]

Answer:

The total percent decrease is $a+b-\frac{a b}{100}$

Step-by-step explanation:

We are given with a word problem
We are asked to find the total percentage decrease
We can do this in two steps

Step 1: Finding the two percentage decrease

Step 2: Finding their difference

Step 1 of 2

Let the decrease by a% be 100-a

Then b% decrease is

$\begin{aligned}\frac{b}{100} \times(100-a) &=\frac{100 b-a b}{100} \\\frac{100 b}{100}-\frac{a b}{100} &=b-\frac{a b}{100}\end{aligned}$

Step 2 of 2

The percentage difference between the two percentages is,

$\begin{aligned}&(100-a)-\left(b-\frac{a b}{100}\right)=100-a-b+\frac{a b}{100} \\&100-a-b+\frac{a b}{100}=100-\left(a+b-\frac{a b}{100}\right)\end{aligned}$

Since 100 is the total percent $a+b-\frac{a b}{100}$ is the percentage decrease.

3 0

1 year ago

Find the third side in simplest radical form: 89 39

Eva8 [605]

89 squared minus 39 squared and the answer you get is what you put into the radical

5 0

3 years ago