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2 years ago

Samantha claims that 4x + 2 is equivalent to the expression x + 17 + 3x − 15.

Mathematics

2 answers:

Nadya [2.5K]2 years ago

7 0

Answer:

Samantha is correct because when using x = 2, the resulting values in both expressions are equal.

Step-by-step explanation:

x + 17 + 3x - 15

x + 3x + 17 - 15 = 4x + 2.

MAVERICK [17]2 years ago

4 0

X + 17 +3x -15

x +3x = 4x

17-15 = 2
which becomes 4x +2 so it is true

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The question is in the image! Please help if u can its due really soon

Leno4ka [110]

Answer:

Angle STR = 78°

Step-by-step explanation:

So, since line QS is a straight line, we know that it's 180°. We also know that angles QTR and STR both add up to 180°. That gives us an equation:

20x + 12 + 10x + 33 = 180

Combine like terms

30x + 45 = 180

Subtract 45 from both sides

30x = 135

Divide both sides by 30

x = 4.5

Now we know the value of x. We just need to plug it into angle STR's given value:

10(4.5) + 33 = angle STR

45 + 33 = angle STR

78° = angle STR

4 0

3 years ago

The mean of 10 values is 19. If further 5 values are

Leokris [45]

Answer:

Step-by-step explanation:

Pretend the 10 values in the first sentence are a,b,c,d,e,f,g,h,i,j

Pretend the addition 5 values is k,l,m,n,o

So the mean of all the 15 data is (a+b+c+d+e+f+g+h+i+j+k+l+m+n+o)/15=20

So the sum of all 15 data is a+b+c+d+e+f+g+h+i+j+k+l+m+n+o=300 since 15(20)=300

Now let's look at the first 10: We have their mean so we can write:

(a+b+c+d+e+f+g+h+i+j)/10=19

so a+b+c+d+e+f+g+h+i+j=190 since 10(19)=190

So that means using our first sum equation and our equation sum equation we have

190+k+l+m+n+o=300

k+l+m+n+o=300-190

k+l+m+n+o= 110

So the average of those 5 numbers mentioned in your problem is 110/5=22

3 0

3 years ago

The weight of an adult swan is normally distributed with a mean of 26 pounds and a standard deviation of 7.2 pounds. A farmer ra

Snezhnost [94]

Let $X$ denote the random variable for the weight of a swan. Then each swan in the sample of 36 selected by the farmer can be assigned a weight denoted by $X_1,\ldots,X_{36}$ , each independently and identically distributed with distribution $X_i\sim\mathcal N(26,7.2)$ .

You want to find

$\mathbb P(X_1+\cdots+X_{36}>1000)=\mathbb P\left(\displaystyle\sum_{i=1}^{36}X_i>1000\right)$

Note that the left side is 36 times the average of the weights of the swans in the sample, i.e. the probability above is equivalent to

$\mathbb P\left(36\displaystyle\sum_{i=1}^{36}\frac{X_i}{36}>1000\right)=\mathbb P\left(\overline X>\dfrac{1000}{36}\right)$

Recall that if $X\sim\mathcal N(\mu,\sigma)$ , then the sampling distribution $\overline X=\displaystyle\sum_{i=1}^n\frac{X_i}n\sim\mathcal N\left(\mu,\dfrac\sigma{\sqrt n}\right)$ with $n$ being the size of the sample.

Transforming to the standard normal distribution, you have

$Z=\dfrac{\overline X-\mu_{\overline X}}{\sigma_{\overline X}}=\sqrt n\dfrac{\overline X-\mu}{\sigma}$

so that in this case,

$Z=6\dfrac{\overline X-26}{7.2}$

and the probability is equivalent to

$\mathbb P\left(\overline X>\dfrac{1000}{36}\right)=\mathbb P\left(6\dfrac{\overline X-26}{7.2}>6\dfrac{\frac{1000}{36}-26}{7.2}\right)$
$=\mathbb P(Z>1.481)\approx0.0693$

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2 years ago

Give one example of the following properties for whole number under addition

Marina CMI [18]

Step-by-step explanation:

Objective: Recall the properties.

a) 3+1=4

b) 3+7=7+3

c) 3+(7+4)=7+(3+4)

d). 3(7+4)=(3×7)+(3×4)

5 0

2 years ago

I need help ASAP will mark you the brainliest

Leokris [45]

Answer:

Step-by-step explanation:

longer leg/shorter leg = longer leg/shorter leg

10/5 = 5/2.5

8 0

3 years ago