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2 years ago

Find the centre and radius for this circle , x^2+y^2=25

Mathematics

1 answer:

aliya0001 [1]2 years ago

3 0

Answer:

centre = (0, 0 ), radius = 5

Step-by-step explanation:

The equation of a circle centred at the origin is

x² + y² = r² ( r is the radius )

x² + y² = 25 ← is in this form

with centre = (0, 0 ) and r = $\sqrt{25}$ = 5

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What is the number 3x1 + 2x

Nastasia [14]

Answer:

troupe ta reponse too meme je ne confused pas mais churches tu va trouver ou tu voie les autres responses correct

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1 year ago

Working alone and at a constant rate, Machine A takes 3 hours to create a widget. Machine B, working alone and at a constant rat

PilotLPTM [1.2K]

Answer:

Time required by Machine B to create a widget = 4 hours

Step-by-step explanation:

Time taken by Machine A ( $T_{A}$ ) = 3 hours

Time taken by Machine B ( $T_{B}$ )= x hours

Time taken by both machines by working together = 12 hours

The time required to both machines by working together to finish a task is given by the formula = $\frac{T_{A} {T_{B} } }{T_{A} + T_{B} }$

Put the values in above formula we get

⇒ T = $\frac{3 x}{3 + x}$

⇒ 12 = $\frac{3 x}{3 + x}$

⇒ 36 + 12 x = 3 x

⇒ x = - 4 hours

This is the time required by Machine B to create a widget.

8 0

3 years ago

The amount of money spent on textbooks per year for students is approximately normal.

Ostrovityanka [42]

Answer:a

$336.04 < \mu < 443.96$

The margin of error will increase

The margin of error will decreases

The 99% confidence interval is $0.4107 < p < 0.4293$

Step-by-step explanation:

From the question we are told that

The sample size $n = 19$

The sample mean is $\= x = \$\ 390$

The standard deviation is $\sigma = \$ \ 120$

Given that the confidence level is 95% then the level of significance is mathematically represented as

$\alpha = 100 - 95$

$\alpha = 5 \%$

$\alpha = 0.05$

Next we obtain the critical value of $\frac{\alpha }{2}$ from the normal distribution table

$Z_{\frac{\alpha }{2} } = 1.96$

The margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} } * \frac{\sigma}{\sqrt{n} }$

=> $E = 1.96 * \frac{120}{\sqrt{19} }$

=> $E = 53.96$

The 95% confidence interval is

$\= x - E < \mu < \= x + E$

=> $390 - 53.96 < \mu < 390 - 53.96$

=> $336.04 < \mu < 443.96$

When the confidence level increases the $Z_{\frac{\alpha }{2} }$ also increases which increases the margin of error hence the confidence level becomes wider

Generally the sample size mathematically varies with margin of error as follows

$n \ \ \alpha \ \ \frac{1}{E^2 }$

So if the sample size increases the margin of error decrease

The sample proportion is mathematically represented as

$\r p = \frac{210}{500}$

$\r p = 0.42$

Given that the confidence level is 0.99 the level of significance is $\alpha = 0.01$

The critical value of $\frac{\alpha }{2}$ from the normal distribution table is

$Z_{\frac{\alpha }{2} } = 2.58$

Generally the margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} }* \sqrt{ \frac{\r p (1- \r p )}{n} }$

=> $E = 0.42 * \sqrt{ \frac{0.42 (1- 0.42 )}{ 500} }$

=> $E = 0.0093$

The 99% confidence interval is

$\r p - E < p < \r p + E$

$0.42 - 0.0093 < p < 0.42 + 0.0093$

$0.4107 < p < 0.4293$

4 0

3 years ago

Cranberry juice costs $6.30 per quart and apple juice costs $3.60 per quart. Terrence wants to know how many quarts q of cranber

riadik2000 [5.3K]

Q = The Ammount Of Cranberry Juice

(q+4)*4.50=q*6.30+4*3.60

4.5*q+18=6.30*q+14.4

6.30*q-4.5*q=18-14.4

1.8*q=3.6

q=3.6/1.8

It Would Be 2 Quarts Of Cranberry Juice

4 0

3 years ago

Chose all the values of x that are not in the domain of this rational function. Picture attached, 15 points and I'll give Brainl

pogonyaev

Answer:

All of them.

Step-by-step explanation:

For rational functions, the domain is all real numbers <em>except</em> for the zeros of the denominator.

Therefore, to find the x-values that are not in the domain, we need to solve for the zeros of the denominator. Therefore, set the denominator to zero:

$x(x-1)(x^2-4)=0$