PLEASE HELP!!! PRE CAL!!!

Natalija [7]

Option D:

$\left(-\frac{2}{5}\right)\left(-\frac{8}{9}\right)\left(\frac{1}{3}\right)\left(\frac{2}{7}\right)$ is positive product.

Solution:

<em>If the negative sign is in even number of times then the product is positive.</em>

<em>If the negative sign is in odd number of times then the product is negative.</em>

To find which product is positive:

Option A:

$$\left(\frac{2}{5}\right)\left(-\frac{8}{9}\right)\left(-\frac{1}{3}\right)\left(-\frac{2}{7}\right)$

Here, number of negative signs = 3

3 is an odd number.

So, the product is negative.

Option B:

$$\left(-\frac{2}{5}\right)\left(\frac{8}{9}\right)\left(-\frac{1}{3}\right)\left(-\frac{2}{7}\right)$

Here, number of negative signs = 3

3 is an odd number.

So, the product is negative.

Option C:

$$\left(\frac{2}{5}\right)\left(\frac{8}{9}\right)\left(\frac{1}{3}\right)\left(-\frac{2}{7}\right)$

Here, number of negative sign = 1

1 is an odd number.

So, the product is negative.

Option D:

$$\left(-\frac{2}{5}\right)\left(-\frac{8}{9}\right)\left(\frac{1}{3}\right)\left(\frac{2}{7}\right)$

Here, number of negative sign = 2

2 is an odd number.

So, the product is positive.

Hence option D is the correct answer.

$\left(-\frac{2}{5}\right)\left(-\frac{8}{9}\right)\left(\frac{1}{3}\right)\left(\frac{2}{7}\right)$ is positive product.

4 0

3 years ago

A culture of 3,000 bacteria quadruples in number every 10 hours. Plt) represents the

Levart [38]

Answer:

P(t) = 3000 * 4^(t/10)

Step-by-step explanation:

There is more than one way to get an exponential function out of the information given. The way the question is worded, however, seems to suggest the following type of answer:

One general form of the exponential function is y = a·bx, where a is the initial value, and b is the growth or decay factor. So right away we can say that a = 2300.

Now for the growth factor. When something is increasing or decreasing by a certain percentage, we are adding or subtracting that percentage to the 100% (which is equal to 1) that exists currently. So here we're increasing by 11%, or 0.11. Then the growth factor b is (1 + 0.11), or 1.11.

4 0

3 years ago

The drill team at Hill Middle School made 120 spirit pins to sell for a fundraiser. After the fundraiser, the team had 18 pins l

Marizza181 [45]

no 1) is 85%

no 2) is 32 - 80 = -48

3 0

3 years ago

G(x)=9x-11 find g(8)

sineoko [7]

Answer:

Step-by-step explanation:

8(9x-11)

72x-88

6 0

3 years ago

Kent is cutting a long tree into pieces. He cut the trunk into 3 pieces. Then he cut each of those pieces into 3 smaller pieces.

VladimirAG [237]

Answer:

27

Step-by-step explanation:

he started by cutting one log into 3

1×3=3

then cutting each of those into 3

3×3=9

then again

9×3=27

6 0

3 years ago