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2 years ago

What is 4x(5x-2)=20x-2

Mathematics

1 answer:

Zanzabum2 years ago

7 0

Answer: x = 1.32 and x= 0.076

Step-by-step explanation:

4x(5x-2) = 20x-2

20x^2-8x = 20x-2

20x^2-8x-20x+2=0

20x^2-28x+2=0

Using quadratic equation

x = (-b +or- √(b^2-4ac))/2a

a =20, b=28, c= 2

Substitute into the equation

x= (7+√39)/10. = 1.32

x = (7-√39)/10 = 0.076

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Find x. I need help please

Misha Larkins [42]

Answer:

$x = 4 \sqrt{3}$

Step-by-step explanation:

By geometric mean theorem and Pythagoras theorem:

${x}^{2} = { (\sqrt{8 \times 4} )}^{2} + {4}^{2} \\ \\ {x}^{2} = { (\sqrt{32} )}^{2} + {4}^{2} \\ \\ {x}^{2} = 32 + 16 \\ \\ {x}^{2} = 48 \\ \\ x = \sqrt{48} \\ \\ x = 4 \sqrt{3}$

3 0

2 years ago

Elimination_4x_2y=14 _10x+7y=_24

Gnesinka [82]

Answer:

The answer is $x=-\frac{50}{8}$ and $y=\frac{11}{2}.$

Step-by-step explanation:

Given:

-4x-2y=14

-10x+7y=-24

Now, to solve it by elimination:

$-4x-2y=14$ ......(1)

$-10x+7y=-24$ ......(2)

So, we multiply the equation (1) by 7 we get:

$-28x-14y=98$

And, we multiply the equation (2) by 2 we get:

$-20x+14y=-48$

Now, adding both the new equations:

$-28x-14y+(-20x+14y)=98+(-48)$

$-28x-14y-20x+14y=98-48$

$-28x-20x-14y+14y=50$

$-8x=50$

Dividing both the sides by -8 we get:

$x=-\frac{50}{8}$

Now, putting the value of $x$ in equation (1):

$-4x-2y=14$

$-4(-\frac{50}{8})-2y=14$

$\frac{200}{8} -2y=14$

$25-2y=14$

Subtracting both sides by 25 we get:

$-2y=-11$

Dividing both sides by -2 we get:

$y=\frac{11}{2}$

Therefore, the answer is $x=-\frac{50}{8}$ and $y=\frac{11}{2}.$

5 0

3 years ago

In a horse race with 5 horses, you make a bet by predicting the ranking of all 5 horses. Suppose you place your bet at random. W

lapo4ka [179]

Answer:

P( top two horses are predicted incorrectly in incorrect order)

= $\frac{1}{2}$

Step-by-step explanation:

In the horse race the outcome can be predicted in 5! = 120 ways.

Now suppose the top two horses were predicted incorrectly in incorrect order. Now, the top horse can be predicted incorrectly in 4 ways.

Suppose the top horse was predicted to be in k-th position where k = 2, 3 ,4,5

so the second horse can be predicted to be in place from 1 to (k - 1)

So, the top two horses can be predicted incorrectly in incorrect order

in $\sum_{k =2}^{5}(k - 1)$ = 10 ways

and for each prediction of the two the remaining horses may be predicted in 3! = 6 ways.

Hence ,

P( top two horses are predicted incorrectly in incorrect order)

= $\frac{6 \times 10}{120}$

= $\frac{1}{2}$

8 0

2 years ago

Find the value of 7v-10 given that -11v-7=4. Simplify your answer as much as possible.

densk [106]

First thing to do is solve the given equation for v

-11v-7 = 4

-11v = 4+7

-11v = 11

v = 11/(-11)

v = -1

Once we know this, we can use it to compute the following

7v-10 = 7*(-1) - 10 = -7 - 10 = -17

--------------------------------

Answer: -17

4 0

2 years ago

Can someone please help You have to solve the proportions . Thanks

Hoochie [10]

Answer:

40.265

Step-by-step explanation:

Divide 5 by 3 and continue dividing or mulitplying the numbers given

numbers on the top row: Mulityply

numbers on the bottom row: Divide

4 0

2 years ago

Read 2 more answers