All categories

2 years ago

What is the sum of (2x^2-8x) and (-x^2-2x) please help me

Mathematics

2 answers:

Vesna [10]2 years ago

8 0

x ² - 10 x

Step-by-step explanation:

( 2 x ² - 8 x ) + ( - x² - 2 x )

2 x ² - 8 x - x ² - 2 x

2 x² - x ² - 8 x - 2 x ..(combine like terms)

x ² - 10 x

Lostsunrise [7]2 years ago

7 0

Answer:

the sum of (2x^2-8x) and (-x^2-2x )

=2x^2-x^2-8x-2x=x^2-10x

You might be interested in

The U.S. Bureau of Labor Statistics released hourly wage figures for various countries for workers in the manufacturing sector.

elena-14-01-66 [18.8K]

Answer:

(a) The probability that the sample average will be between $30.00 and $31.00 is 0.5539.

(b) The probability that the sample average will exceed $21.00 is 0.12924.

(c) The probability that the sample average will be less than $22.80 is 0.04006.

Step-by-step explanation:

We are given that the hourly wage was $30.67 for Switzerland, $20.20 for Japan, and $23.82 for the U.S.

Assume that in all three countries, the standard deviation of hourly labor rates is $4.00.

(a) Suppose 40 manufacturing workers are selected randomly from across Switzerland.

Let $\bar X$ = sample average wage

The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean wage for Switzerland = $30.67

$\sigma$ = standard deviation = $4.00

n = sample of workers selected from across Switzerland = 40

Now, the probability that the sample average will be between $30.00 and $31.00 is given by = P($30.00 < $\bar X$ < $31.00)

P($30.00 < $\bar X$ < $31.00) = P( $\bar X$ < $31.00) - P( $\bar X$ $\leq$ $30.00)

P( $\bar X$ < $31) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < $\frac{31-30.67}{\frac{4}{\sqrt{40} } }$ ) = P(Z < 0.52) = 0.69847

P( $\bar X$ $\leq$ $30) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ $\leq$ $\frac{30-30.67}{\frac{4}{\sqrt{40} } }$ ) = P(Z $\leq$ -1.06) = 1 - P(Z < 1.06)

= 1 - 0.85543 = 0.14457

The above probability is calculated by looking at the value of x = 0.52 and x = 1.06 in the z table which has an area of 0.69847 and 0.85543 respectively.

Therefore, P($30.00 < $\bar X$ < $31.00) = 0.69847 - 0.14457 = 0.5539

(b) Suppose 32 manufacturing workers are selected randomly from across Japan.

Let $\bar X$ = sample average wage

The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean wage for Japan = $20.20

$\sigma$ = standard deviation = $4.00

n = sample of workers selected from across Japan = 32

Now, the probability that the sample average will exceed $21.00 is given by = P( $\bar X$ > $21.00)

P( $\bar X$ > $21) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ > $\frac{21-20.20}{\frac{4}{\sqrt{32} } }$ ) = P(Z > 1.13) = 1 - P(Z < 1.13)

= 1 - 0.87076 = 0.12924

The above probability is calculated by looking at the value of x = 1.13 in the z table which has an area of 0.87076.

(c) Suppose 47 manufacturing workers are selected randomly from across United States.

Let $\bar X$ = sample average wage

The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean wage for United States = $23.82

$\sigma$ = standard deviation = $4.00

n = sample of workers selected from across United States = 47

Now, the probability that the sample average will be less than $22.80 is given by = P( $\bar X$ < $22.80)

P( $\bar X$ < $22.80) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < $\frac{22.80-23.82}{\frac{4}{\sqrt{47} } }$ ) = P(Z < -1.75) = 1 - P(Z $\leq$ 1.75)

= 1 - 0.95994 = 0.04006

The above probability is calculated by looking at the value of x = 1.75 in the z table which has an area of 0.95994.

3 0

3 years ago

146 Mathe Functional skills Level 1 Diagnostic

geniusboy [140]

Answer:

Step-by-step explanation:

56-25=31

6 0

3 years ago

Read 2 more answers

Convert the following equation to slope-intercept form to graph. 7x – y = –3

jekas [21]

Slope-intercept form:
y = m x + b
7 x - y = - 3
- y = - 7 x - 3 / * ( - 1 )( we have to multiply both sides of the equation by - 1 )
Answer:
y = 7 x + 3

8 0

3 years ago

harry invests £6000 in a savings account. the account pays 3.4% compound interest per year. work out the value of his investment

Nataly_w [17]

Invested amount (P0 = £6000.

Rate of interest (r) = 3.4% = 0.034.

We know compound interest formula

A = P(1+r)^t

We need work out the value of his investment per year.

So, we need to plug t=1 and plugging values of P and r in the formula above, we get

A = 6000(1+0.034)^1

A = 6000(1.034)

A = 6204.

<h3>Therefore, the value of his investment per year is £ 6204.</h3>

Now, we need to work out the value of his investment after 3 years.

So, we need to plug t=3.

A = 6000(1+0.034)^3

A = 6000(1.034)^3

1.034^3=1.105507304

A = 6000 × 1.105507304

A = 6633.04

<h3>Therefore, the value of his investment after 3 year is £ 6633.04.</h3>

6 0

2 years ago

Mike has a total of 50 quarters and dimes. The coins total value is $10.55. How many quarters

Mariana [72]

Answer:

Mike will only need 42 quarters to make 10.50

Step-by-step explanation:

3 0

2 years ago