I dont understand the math answer can you explain better please.

What is the value of expression MATH HELP

iris [78.8K]

All of the answer choices that you are given are incorrect. I have calculated it in all different ways and get the same thing and it is none of those. The correct answer would be -75 though.

7 0

3 years ago

Given the equation 5x − 4 = –2(3x + 2), solve for the variable. Explain each step and justify your process.

blagie [28]

A.
$5x-4=-2(3x+2) \ \ \ \ \ \ \ \ \ |\hbox{expand the bracket} \\
5x-4=-2 \times 3x-2 \times 2 \\
5x-4=-6x-4 \ \ \ \ \ \ \ \ \ \ \ \ \ |\hbox{add 6x to both sides} \\
11x-4=-4 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\hbox{add 4 to both sides} \\
11x=0 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\hbox{divide both sides by 11} \\
x=0$

B.
$3(2x-4)=5x-1 \\
6x-12=5x-1 \\
\boxed{11x-12=-1} \Leftarrow \hbox{the first mistake} \\
11x=11 \\
\boxed{x=11} \Leftarrow \hbox{the second mistake}$

Megan's solution isn't correct.
The first mistake: she subtracted 5x from the right-hand side of the equation, but added 5x to the left-hand side.
The second mistake: she divided the right-hand side of the equation by 11, but didn't divide the left-hand side.

The correct solution:
$3(2x-4)=5x-1 \ \ \ \ \ \ \ \ \ \ \ |\hbox{expand the bracket} \\
3 \times 2x+3 \times (-4)=5x-1 \\ 6x-12=5x-1 \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\hbox{subtract 5x from both sides} \\
x-12=-1 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\hbox{add 12 to both sides} \\
x=11$

3 0

3 years ago

A spyware is trying to break into a system by guessing its password. It does not give up until it tries 1 million different pass

Anettt [7]

Answer:

$Probability = 0.006033$

Step-by-step explanation:

Given

$Tries = 1000000$

Required

Determine the probability of 6 different lower case letters (Question continuation)

There are 26 lower case letters.

The first can be any of letters 26

The second can be any of letters 26 - 1

The third can be any of letters 26 - 2

The fourth can be any of letters 26 - 3

The fifth can be any of letters 26 - 4

The sixth can be any of letters 26 - 5

Number of selection is:

$Selection = 26 * (26 - 1) * (26 - 2) * (26 - 3) * (26 - 4) * (26 - 5)$

$Selection = 26 * 25 * 24 * 23 * 22 * 21$

$Selection = 165765600$

The probability is:

$Probability = \frac{Tries}{Selection}$

$Probability = \frac{1000000}{165765600}$

$Probability = 0.00603261472$

$Probability = 0.006033$ --- approximated

6 0

2 years ago

Ln how many ways 5 person sitted in a round table having 8 seats?

kvasek [131]

Answer: First consider the case that ‘just’ 5 persons are seated around a round table.

Clearly, ‘just’ 5 persons can be seated around a round table in (5 - 1)! = 4! = 24 ways.

Now, one vacant chair is to be inserted among them.

Say, for a particular sitting arrangement ‘ABCDE’; there are 5 scopes available for inserting the vacant chair - between A and B, between B and C, between C and D, between D and E & between E and A.

So, there are 5*24 = 120 ways available that 5 persons can sit around a round table with 6 chairs.

Step-by-step explanation:

First consider the case that ‘just’ 5 persons are seated around a round table.

Clearly, ‘just’ 5 persons can be seated around a round table in (5 - 1)! = 4! = 24 ways.

Now, one vacant chair is to be inserted among them.

Say, for a particular sitting arrangement ‘ABCDE’; there are 5 scopes available for inserting the vacant chair - between A and B, between B and C, between C and D, between D and E & between E and A.

So, there are 5*24 = 120 ways available that 5 persons can sit around a round table with 6 chairs.

5 0

3 years ago

£72 shared in the ratio of 2:7

Goryan [66]

To do that we have to add 2+7=9
Next step is to divide 72 by 9
72:9=8 - its how many pounds its in"1"
Finally we can multiply
2*8=16
7*8=56 - its the answer

8 0

3 years ago