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3 years ago

At what point does the line with equation y=4-2x cut the y axis?

Mathematics

1 answer:

Mila [183]3 years ago

7 0

Answer:

Step-by-step explanation:

This equation is in a reversed form of slope-intercept, or y=mx+b. In this form, b is the y-intercept and in the equation b is equal to 4 and the slop is 2!

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Please help me out :)

NeTakaya

1. D
2.B
3.A
4. D i think i can’t really see that question
5.C

5 0

3 years ago

Chole is baking cookies to sell in boxes of 12 cookies.If she bakes 112 cookies, calculate the number of boxes she can fill and

Grace [21]

Answer:

She can fill 9 boxes, and will have 4 cookies left over.

Step-by-step explanation:

9 x 12 = 108.

112 - 108 = 4

5 0

3 years ago

A metal beam was brought from the outside cold into a machine shop where the temperature was held at 65degreesF. After 5 min, t

ivolga24 [154]

Answer:

The beam initial temperature is 5 °F.

Step-by-step explanation:

If T(t) is the temperature of the beam after t minutes, then we know, by Newton’s Law of Cooling, that

$T(t)=T_a+(T_0-T_a)e^{-kt}$

where $T_a$ is the ambient temperature, $T_0$ is the initial temperature, $t$ is the time and $k$ is a constant yet to be determined.

The goal is to determine the initial temperature of the beam, which is to say $T_0$

We know that the ambient temperature is $T_a=65$ , so

$T(t)=65+(T_0-65)e^{-kt}$

We also know that when $t=5 \:min$ the temperature is $T(5)=35$ and when $t=10 \:min$ the temperature is $T(10)=50$ which gives:

$T(5)=65+(T_0-65)e^{k5}\\35=65+(T_0-65)e^{-k5}$

$T(10)=65+(T_0-65)e^{k10}\\50=65+(T_0-65)e^{-k10}$

Rearranging,

$35=65+(T_0-65)e^{-k5}\\35-65=(T_0-65)e^{-k5}\\-30=(T_0-65)e^{-k5}$

$50=65+(T_0-65)e^{-k10}\\50-65=(T_0-65)e^{-k10}\\-15=(T_0-65)e^{-k10}$

If we divide these two equations we get

$\frac{-30}{-15}=\frac{(T_0-65)e^{-k5}}{(T_0-65)e^{-k10}}$

$\frac{-30}{-15}=\frac{e^{-k5}}{e^{-k10}}\\2=e^{5k}\\\ln \left(2\right)=\ln \left(e^{5k}\right)\\\ln \left(2\right)=5k\ln \left(e\right)\\\ln \left(2\right)=5k\\k=\frac{\ln \left(2\right)}{5}$

Now, that we know the value of $k$ we can use it to find the initial temperature of the beam,

$35=65+(T_0-65)e^{-(\frac{\ln \left(2\right)}{5})5}\\\\65+\left(T_0-65\right)e^{-\left(\frac{\ln \left(2\right)}{5}\right)\cdot \:5}=35\\\\65+\frac{T_0-65}{e^{\ln \left(2\right)}}=35\\\\\frac{T_0-65}{e^{\ln \left(2\right)}}=-30\\\\\frac{\left(T_0-65\right)e^{\ln \left(2\right)}}{e^{\ln \left(2\right)}}=\left(-30\right)e^{\ln \left(2\right)}\\\\T_0=5$

so the beam started out at 5 °F.

6 0

3 years ago

A line for tickets to a Broadway show had a mean waiting time of 20 minutes with a standard deviation of 5 minutes.

andrezito [222]

Answer:

5.48% of the people in line waited for more than 28 minutes

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean waiting time of 20 minutes with a standard deviation of 5 minutes.

This means that $\mu = 20, \sigma = 5$

What percentage of the people in line waited for more than 28 minutes?

The proportion is 1 subtracted by the p-value of Z when X = 28. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{28 - 20}{5}$

$Z = 1.6$

$Z = 1.6$ has a p-value of 0.9452.

1 - 0.9452 = 0.0548.

As a percentage:

0.0548*100% = 5.48%

5.48% of the people in line waited for more than 28 minutes

6 0

2 years ago

În Figura 2 este reprezentat un trapez isoscel ABCD cu AB paralel CD , AC perpendicular BD, AB = 8m, CD = 4m . Punctele M , N ,

solong [7]

Answer:

Step-by-step explanation:

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8 0

3 years ago