All categories

3 years ago

Explain why this is wrong:

Mathematics

1 answer:

marin [14]3 years ago

5 0

Answer:

See below.

Step-by-step explanation:

y^2 - 6y + 9 can be changed correctly into y^2 - 2(y)(3) + 3^2.

Up to here, it's correct.

The right side above shows a polynomial that is the square of a binomial.

It factors into (y - 3)^2.

The correct factorization is (y - 3)^2.

The incorrect factorization of the student's solution is the product of a sum and difference.

The product of a sum and a difference is the correct factorization for a difference of squares.

For example, y^2 - 9 is the same as y^2 - 3^2 and is a difference of squares.

It factors into (y + 3)(y - 3), a product of a sum and a difference.

You might be interested in

Consider a data set containing the following values: 70 65 71 78 89 68 50 75 The mean of the preceding values is 70.75. The devi

Leokris [45]

Answer:

If this is the sample data, the sample variance is 125.07 and the sample standard deviation is 11.18

If this is a population data, the population variance is 109.44 and the population standard deviation is 10.46

Step-by-step explanation:

We are given the following data-set:

70, 65, 71, 78, 89, 68, 50, 75

Deviations from the mean

–0.75, –5.75 , 0.25, 7.25, 18.25, –2.75, –20.75, 4.2

Sample size, n = 8

Sample:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n-1}}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

Sum of squares of differences =

0.5625 + 33.0625 + 0.0625 + 52.5625 + 333.0625 + 7.5625 + 430.5625 + 18.0625 = 875.5

$s = \sqrt{\dfrac{875.5}{7}} = 11.18$

$\text{ Sample variance} = s^2 = 125.07$

Population:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

Sum of squares of differences =

0.5625 + 33.0625 + 0.0625 + 52.5625 + 333.0625 + 7.5625 + 430.5625 + 18.0625 = 875.5

$\sigma = \sqrt{\dfrac{875.5}{8}} = 10.46$

$\text{ Population variance} = \sigma^2 = 109.44$

7 0

3 years ago

Let U={q, r, s, t, u, V, W, X, Y, Z},

trapecia [35]

Answer:

Ooh is theis unions I did it but

3 0

2 years ago

Write an equation of the line containing the point (3,1) and perpendicular to the line 5x-3y=5

dusya [7]

Th answer is: y=-1/5x+8/5

7 0

3 years ago

Can someone help with this question

egoroff_w [7]

M = (t+1)/(t-3)
m(t-3) = t+1
mt-3m = t+1
(m-1)t = 3m+1
t = (3m+1)/(m-1)

4 0

3 years ago

jo goes to a restaurant for a meal. there are 5 starters and 7 main courses to choose from. Jo chooses a starter and a main cour

saveliy_v [14]

Answer:

35 combinations of a starter and a main course.

Step-by-step explanation:

1a, 1b, 1c, 1d, 1e, 1f, 1g

2a, 2b, 2c, 2d, 2e, 2f, 2g

3a, 3b, 3c, 3d, 3e, 3f, 3g

4a, 4b, 4c, 4d, 4e, 4f, 4g

5a, 5b, 5c, 5d, 5e, 5f, 5g

i hope this helps

7 0

3 years ago