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Verdich [7]
3 years ago
6

Solve this system of equations using substitution:

Mathematics
1 answer:
yanalaym [24]3 years ago
4 0
I’m thinking your r in the first equation is actually an x.

X + 2(2x -4) =10

X +4x -8 =10

5x = 18

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Write the equation of a line with a y intercept of (5,0) that goes through the points (2,6) and (-1,12)
kodGreya [7K]

Answer:

it goes diagnoly

Step-by-step explanation:

because

7 0
3 years ago
PTC is a substance that has a strong bitter taste for some people and is tasteless for others. The ability to taste PTC is inher
lana66690 [7]

Answer:

a) n=\frac{0.76(1-0.76)}{(\frac{0.01}{1.64})^2}=4905.83  

And rounded up we have that n=4906

b) For this case since we don't have prior info we need to use as estimatro for the proportion \hat p =0.5

n=\frac{0.5(1-0.5)}{(\frac{0.01}{1.64})^2}=6724  

And rounded up we have that n=6724

Step-by-step explanation:

We need to remember that the confidence interval for the true proportion is given by :  

\hat p \pm z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}

Part a

The estimated proportion for this case is \hat p =0.76

Our interval is at 90% of confidence, and the significance level is given by \alpha=1-0.90=0.1 and \alpha/2 =0.05. The critical values for this case are:

z_{\alpha/2}=-1.64, t_{1-\alpha/2}=1.64

The margin of error for the proportion interval is given by this formula:  

ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}    (a)  

The margin of error desired is given ME =\pm 0.01 and we are interested in order to find the value of n, if we solve n from equation (a) we got:  

n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}   (b)  

Replacing we got:

n=\frac{0.76(1-0.76)}{(\frac{0.01}{1.64})^2}=4905.83  

And rounded up we have that n=4906

Part b

For this case since we don't have prior info we need to use as estimatro for the proportion \hat p =0.5

n=\frac{0.5(1-0.5)}{(\frac{0.01}{1.64})^2}=6724  

And rounded up we have that n=6724

3 0
3 years ago
On Tuesday Emily bought four posters,
hram777 [196]

Answer: 16 posters

Step-by-step explanation:

Monday - Had owned 16 posters

Tuesday - Bought 4 posters, adding up to 20

Wednesday - Half of the posters were destroyed, half of 20 is 10

Thursday - 10 posters remained.

8 0
3 years ago
Read 2 more answers
Easy question i will mark braineliest
Yuki888 [10]

Answer:

<h2>0.67</h2>

Step-by-step explanation:

5(y - 3.8) = 4.7(y - 4)

Distribute 5 through the parentheses

5y - 19 = 4.7(y - 4)

Distribute 4.7 through the parentheses

5y - 19 = 4.7y - 18.8

Move ' 4.7 y ' to L.H.S and change it's sign

5y - 4.7y - 19 =  - 18.8

Move constant to R.H.S and change it's sign

5y - 4.7y =  - 18.8 + 19

Collect like terms

0.3y =  - 18.8 + 19

Calculate

0.3y = 0.2

Divide both sides of the equation by 0.3

\frac{0.3y}{0.3}  =  \frac{0.2}{0.3}

Calculate

y = 0.67

Hope this helps...

Best regards!!

3 0
3 years ago
Read 2 more answers
The discount on a new stereo was $180. This was a discount of 18%. What was the original selling price?
vladimir2022 [97]

Answer:

$212.40

Step-by-step explanation:

180+ (180* 18%)= Total Cost

180+ 32.40= Total Cost

212.40= Total Cost

8 0
3 years ago
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