Use the grouping method to factor the polynomial below completely.

AB and BC share point B to form AC. If AC=7 and BC=5, then what is the length of AB?

AnnZ [28]

$|AC|=7;\ |BC|=5\\\\|AC|=|AB|+|BC|\\\\|AB|+5=7\ \ \ \ \ |subtract\ 5\ from\ both\ sides\\\\\boxed{|AB|=2}$

4 0

3 years ago

Read 2 more answers

Nick decided to take 2/5 of the money in his bank account and donate it to a local charity. If nick donated $70 to a local chari

S_A_V [24]

Answer:

The total amount = $175

Step-by-step explanation:

Let the total amount in his bank account = x

Nick decided to take 2/5 of the money in his bank account and donate it to a local charity

So, he donates with $\frac{2}{5} x$

If nick donated $70 to a local charity

so, $\frac{2}{5} x = 70$

solve for x

∴ x = 5*70/2 = 350/2 = $175

So, The total amount = $175

3 0

2 years ago

Scores of an IQ test have a bell-shaped distribution with a mean of 100 and a standard deviation of 13. Use the empirical rule

Yuri [45]

Answer:

(a) 68% of people has an IQ score between 87 and 113.

(b) 5% of people has an IQ score less than 74 or greater than 126.

(c) 0.15% of people has an IQ score greater than 139.

Step-by-step explanation:

Given information:Scores of an IQ test have a bell-shaped distribution,

mean = 100

standard deviation = 13

According to the empirical rule

68% data lies between $\overline{x}-\sigma$ and $\overline{x}+\sigma$ .

95% data lies between $\overline{x}-2\sigma$ and $\overline{x}+2\sigma$ .

99.7% data lies between $\overline{x}-3\sigma$ and $\overline{x}+3\sigma$ .

(a)

$\overline{x}-\sigma=100-13=87$

$\overline{x}+\sigma=100+13=113$

$[\overline{x}-\sigma,\overline{x}+\sigma]=[87,113]$

Using empirical rule we can say that 68% of people has an IQ score between 87 and 113.

(b)

$\overline{x}-2\sigma=100-2(13)=74$

$\overline{x}+2\sigma=100+2(13)=126$

$[\overline{x}-2\sigma,\overline{x}+2\sigma]=[74,126]$

Using empirical rule we can say that 95% of people has an IQ score between 74 and 126.

The percentage of people has an IQ score less than 74 or greater than 126 is

P = 1- percent of people has an IQ score between 74 and 126.

P = 1- 95%

P = 5%

Therefore 5% of people has an IQ score less than 74 or greater than 126.

(c)

$\overline{x}-3\sigma=100-3(13)=61$

$\overline{x}+3\sigma=100+3(13)=139$

$[\overline{x}-3\sigma,\overline{x}+3\sigma]=[61,139]$

Using empirical rule we can say that 99.7% of people has an IQ score between 61 and 139.

The percentage of people has an IQ score less than 61 or greater than 139 is

P = 1- percent of people has an IQ score between 61 and 139.

P = 1- 99.7%

P = 0.3%

The percentage of people has an IQ score greater than 139 is

$P=\frac{1}{2}(0.3\%)=0.15\%$

Therefore 0.15% of people has an IQ score greater than 139.

5 0

3 years ago

Which one of these is a square number? 15 39 81 132

coldgirl [10]

81 = 9^2

I hope it's help you...

Thanks♥♥

7 0

2 years ago

Read 2 more answers

Lin ran 2 3/4 miles in 2/5 of an hour. Noah ran 8 2/3 miles in 4/3 of an hour.

sveticcg [70]

(The second one)
Noah ran 8.67 miles in 1 hour and 20 minutes
If we convert the fraction to a decimal (for the miles part) we get 8.67 or 8 2/3 miles.

If 1/3 of an hour is 20 minutes, and an hour is 60 minutes, we add 20 4 times, which gets us to 80, which is 20 past an hour.

6 0

2 years ago