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3 years ago

Consider the expressions 3x(x − 2) + 2 and 2x2 + 3x − 18.

Mathematics

1 answer:

Rzqust [24]3 years ago

4 0

Answer:

See answer below

Step-by-step explanation:

For the first expression

3 x (x - 2) + 2 = 3 x^2 - 6 x + 2

evaluated at x= 4 we get: 26

and for x = 5 we get 47.

For the second expression

2 x^2 + 3 x - 18

we get the exact same values when doing the evaluation at these two points.

Based on those results, one may think the expressions may be equivalent, but they are not equivalent. Because at any other x-value, their results are different. See for example that for x = 0 the first one gives "2" while the second one gives -18.

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These are the heights of 20 plants.

12345 [234]

Answer:

te mean is 5

median is 12

avarae is 6

Step-by-step explanation:

6 0

3 years ago

Find the measure of the missing angle <br> Answer: a=

statuscvo [17]

Answer:

C + 88 = 180

-88 -88

C and B = 92

Since C is vertical to B that means both values are the same. Therefore the values of c and b is 92 degrees.

6 0

3 years ago

Please help me!<br> Find the number x such that f(x) =1

STatiana [176]

Answer:

Step-by-step explanation:

We have the piecewise function:

$f(x) = \left\{ \begin{array}{ll} -\frac{1}{2}x-1 & \quad x \leq -2 \\ x & \quad x > -2 \end{array} \right.$

And we want to find x such that f(x)=1.

So, let's substitute 1 for f(x):

$1 = \left\{ \begin{array}{ll} -\frac{1}{2}x-1 & \quad x \leq -2 \\ x & \quad x > -2 \end{array} \right.$

This has two equations. So, we can separate them into two separate cases. Namely:

$1=-\frac{1}{2}x-1\text{ or } 1=x$

Let's solve for x in each case.

Case I:

We have:

$1=-\frac{1}{2}x-1$

Add 1 to both sides:

$2=-\frac{1}{2}x$

Let's cancel out the fraction by multiplying both sides by -2. So:

$2(-2)=(-2)\frac{-1}{2}x$

The right side cancels:

$-4=x\\$

Flip:

$x=-4$

So, x is -4.

Case II:

We have:

$1=x$

Flip:

$x=1$

This is the solution for our second case.

So, we have:

$x_1=-4\text{ or } x_2=1$

Now, can check to see if we have to to remove solution(s) that don't work.

Note that x=-4 is the solution to our first equation.

The first equation is defined only if x is less than -2.

-4 <em>is </em>less than -2. So, x=-4 is indeed a solution.

x=1 is the solution to our second equation.

The second equation is defined only if x is greater than or equal to -2.

1 <em>is</em> greater than or equal to -2. So, x=1 is <em>also </em>a solution.

Therefore, our two solutions are:

$x_1=-4\text{ or } x_2=1$

Out of our answer choices, we can pick D.

And we're done!

7 0

3 years ago

Your start-up business is looking into the energy usage in the community of south lawndale. your sample size is 12 months. use t

Aleonysh [2.5K]

The confidence interval at 95% level is

7106.87 < μ< 14255.27

<h3>What is meant be mean and standard deviation?</h3>

The ratio of sum of observations to the total number of observation is known as mean. It is one of the central tendency in the statistics. It gives an idea about the central value present in the data. The most sensitive measure of central tendency is mean. It is very easy to calculate. Mean playa a crucial role in daily life. The two types of means are Arithmetic mean and Geometric mean.

Standard deviation is a measure in the statistics. The amount of variation of a set of values is known as standard deviation. Standard deviation is denoted by σ.

As per given data

90% confident level for amount of electricity used in community of Austin is

X-tx/2(n-1)s/√n < μ < X+ tx/2(n-1)s/√n

Here , n=12 , X=10681.07 , s=6893.87

Margin of error = tx/2(n-1)s/√n

=(1.796×6893.87)/√12

=3574.1996

=3574.19(approximately)

Therefore, 90% CI is,

10681.07-3574.19 ≤ μ<10681.07+3574.19

7106.87 < μ< 14255.27

To know more about mean and standard deviation, visit:

brainly.com/question/14720855

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5 0

1 year ago

Can someone please explain to me how to bo this problem? It’s due tomorrow

Lena [83]

Are you trying to simplify? if so, the answer is 13u/6

7 0

3 years ago

Read 2 more answers