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2 years ago

W^2-8w=9 complete the square and round to the nearest hundredth if necessary

Mathematics

1 answer:

Gnoma [55]2 years ago

7 0

Answer:

w = 7, 1

Step-by-step explanation:

A perfect square is shown by a²-2ab+b²

If you substitute the question into the formula you get:

w²-(2×4×w)+4²

Simplify and you get:

w²-8w+16=9

Factor:

(w-4)²=9

Square Root both sides:

w-4=±3

w=7, w=1

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Write a paragraph proof that 1+1=2 (Fun fact: it took over 72 pages just to prove that 1+1=2)

Irina18 [472]

Answer:

The theorem here is essentially that

if a and 3 are disjoint sets with

exactly one element each, then their

union has exactly two elements. ...

Peano shows that it's not hard to

produce a useful set of axioms that

can prove 1+1=2 much more easily

than Whitehead and Russell do.

3 0

2 years ago

Read 2 more answers

Solve each equation.Show your work. Can someone help me please??

Inga [223]

Answer:

1/2a = -5

a = (-5 x 2) : 1

a = -10

8 - b = 9,5

b = 8 - 9,5

b = -1,25

0,1 = -10c

c = 0,1 : -10

c = -0,01

I hope it's helpful.

3 0

3 years ago

The Frosty Ice-Cream Shop sells sundaes for $2 and banana splits for $3. On a hot summer day, the shop sold 8 more sundaes than

svlad2 [7]

The shop sold 36 sundaes and 28 banana spilts

Solution:

Let "a" be the number of sundaes sold

Let "b" be the number of banana spilts sold

Cost of 1 sundaes = $ 2

Cost of 1 banana spilt = $ 3

On a hot summer day, the shop sold 8 more sundaes than banana splits and made $156

Therefore,

Number of sundaes sold = 8 + number of banana spilts sold

a = 8 + b ------- eqn 1

Also, given that they made $ 156

Therefore, we frame a equation as:

Number of sundaes sold x Cost of 1 sundaes + number of banana spilts sold x Cost of 1 banana spilt = 156

$a \times 2+b \times 3 = 156$

2a + 3b = 156 ---------- eqn 2

Substitute eqn 1 into eqn 2

2(8 + b) + 3b = 156

16 + 2b + 3b = 156

16 + 5b = 156

5b = 156 - 16

5b = 140

Substitute b = 28 in eqn 1

a = 8 + 28

Thus the shop sold 36 sundaes and 28 banana spilts

4 0

3 years ago

Pls help extra points and mark brainlist

igor_vitrenko [27]

Answer:

2over/a -b-c

Step-by-step explanation:

remove the parentheses

5 0

3 years ago

The lifetime of a certain type of battery is normally distributed with mean value 10 hours and standard deviation 1 hour. There

Oksi-84 [34.3K]

Answer:

$z=1.64$

And if we solve for a we got;

$10 +1.64*1=11.64$

So the value of height that separates the bottom 95% of data from the top 5% is 11.64

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent certain lifetime of a population, and for this case we know the distribution for X is given by:

$X \sim N(10,1)$

Where $\mu=10$ and $\sigma=1$

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.05$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.95 of the area on the left and 0.05 of the area on the right it's z=1.64. On this case P(Z<1.64)=0.95 and P(z>1.64)=0.05

If we use condition (b) from previous we have this:

$P(X$

$P(z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=1.64$

And if we solve for a we got;

$10 +1.64*1=11.64$

So the value of height that separates the bottom 95% of data from the top 5% is 11.64

4 0

3 years ago