Write the number in standard form? 7.1 x10^4=

HELP PLEASE AND SHOW WORK!!!

lana66690 [7]

Answer:

awnser is A

Step-by-step explanation:

Multiply all sides by 2 then add then up and you get 432.

5 0

2 years ago

A shopkeeper buys two types of tea one at $20 for 10 kg and the other at $23 for 10 kg. He mixes the two types and the mixture i

lorasvet [3.4K]

Let us take the case of first type of tea
Cost of 10 kg of tea one = $20
Then
Cost of 1 kg of tea one = (20/10) dollars
   = 2 dollars
Now let us take the case of the second kind of tea
Cost of 10 kg of tea = $23
Then
Cost of 1 kg of tea = (23/10) dollars
   = 2.3 dollars
So
The mixture of 1 kg of tea one
and 1 kg of second type of tea will cost = (2.0 + 2.3) dollars
      = 4.3 dollars
Then the cost of 2kg mixture of tea costs = 4.3 dollars
So
The cost of 10 kg mixture will cost = (4.3/2) * 10 dollars
   = 4.3 * 5 dollars
      = 21.5 dollars
Then
The amount of profit made by selling 10 kg tea at $38 = (38 - 21.5) dollars
   = 16.5 dollars
So
Percentage of profit made = (16.5/21.5) * 100
   = 1650/21.5
   = 76.74 percent
So the percentage of profit made is 76.74%.

3 0

3 years ago

In the expansion (ax+by)^7, the coefficients of the first two terms are 128 and -224, respectively. Find the values of a and b

madam [21]

Answer:

a = 2, b = 3.5

Step-by-step explanation:

Expanding $(ax+by)^7$ using Binomial expansion, we have that:

$(ax+by)^7$ =

$(ax)^7(by)^0 + (ax)^6(by)^1 + (ax)^5(by)^2 + (ax)^4(by)^3 + (ax)^3(by)^4 + (ax)^2(by)^5 + (ax)^1(by)^6 + (ax)^0(by)^7$

$= (a)^7(x)^7+ (a)^6(x)^6(b)(y) + (a)^5(x)^5(b)^2(y)^2 + (a)^4(x)^4(b)^3(y)^3 + (a)^3(x)^3(b)^4(y)^4 + (a)^2(x)^2(b)^5(y)^5 + (a)(x)(b)^6(y)^6 + (b)^7(y)^7\\\\\\= (a)^7(x)^7+ (a)^6(b)(x)^6(y) + (a)^5(b)^2(x)^5(y)^2 + (a)^4(b)^3(x)^4(y)^3 + (a)^3(b)^4(x)^3(y)^4 + (a)^2(b)^5(x)^2(y)^5 + (a)(b)^6(x)(y)^6 + (b)^7(y)^7$

We have that the coefficients of the first two terms are 128 and -224.

For the first term:

=> $a^7 = 128$

=> $a = \sqrt[7]{128}\\ \\\\a = 2$

For the second term:

$a^6b = -224$

$b = \frac{-224}{a^6}$

$b = \frac{-224}{2^6} \\\\\\b = \frac{-224}{64} \\\\\\b = 3.5$

Therefore, a = 2, b = 3.5

5 0

2 years ago

Solve the equation 6w2 – 7w – 20 = 0.

azamat

For this case we have the following quadratic equation:

$6w ^ 2-7w-20 = 0$

Where:

$a = 6\\b = -7\\c = -20$

Its roots will be given by:

$w = \frac {-b \pm \sqrt {b ^ 2-4 (a) (c)}} {2 (a)}\\w = \frac {- (- 7) \pm \sqrt {(- 7) ^ 2-4 (6) (- 20)}} {2 (6)}\\w = \frac {7 \pm \sqrt {49 + 480}} {12}\\w = \frac {7 \pm \sqrt {529}} {12}\\w = \frac {7 \pm23} {12}$

The roots are:

$w_ {1} = \frac {7 + 23} {12} = \frac {30} {12} = \frac {15} {6} = \frac {5} {2}\\w_ {2} = \frac {7-23} {12} = \frac {-16} {12} = - \frac {8} {6} = - \frac {4} {3}$

Answer:

$w_ {1} = \frac {5} {2}\\w_ {2} = - \frac {4} {3}$

7 0

3 years ago

Read 2 more answers

Use elimination to solve each system of equations.<br><br> 1. 3x+4y=29<br> 6x+5y=43

kakasveta [241]

Answer:

Step-by-step explanation:

3x+4y=29 .......(1)

6x+5y=43 .......(2)

Multiply equation (1) by 2

6x + 8y = 58......(3)

Substracting (2) from (3)

8y - 5y = 58 - 43

3y = 15

Dividing by 3

3y/3 = 15/3

y = 5

Substituting y = 5 into (2)

6x+5y=43

6x + 5(5) = 43

6x + 25 = 43

6x = 43 - 25

6x = 18

Dividing by 6

6x/6 = 18/6

x = 3

4 0

2 years ago