Please help me with this question I would really appreciate it!!!

8X +6Y+4 Y=-3X+9 using substitution what numbers are the variables X and Y

Svetach [21]

Answer:

(5,6)

Step-by-step explanation:

8X +6Y=4

Y=-3X+9

Substitute the second equation into the first. Every place you see y put -3x+9)

8x +6(-3x+9)=4

Distribute

8x-18x +54 = 4

Combine like terms

-10x +54 = 5

Subtract 54 from each side

-10x +54-54=4-54

-10x = -50

Divide by -10

-10x/-10 = -50/-10

x= 5

Now we need to find y

y = -3x+9

y = -3(5) +9

y = -15+9

y= 6

(5,6)

6 0

3 years ago

The school production of Our Town' was a big success. For opening night. 434 tickets were sold. Students paid $4.00 each, while

Alex73 [517]

Answer:

286 students attended

148 non students attended

Step-by-step explanation:

Given

$Tickets = 434$

$Students = \$4.00$

$Non-Students = \$6.00$

$Total = \$2032.00$

Solving (a): Number of students

Represent students with S and non students with N

So:

$S + N = 434$ --- (1)

$4S + 6N = 2032$ --- (2)

Make N the subject of formula in (1)

$N = 434 - S$

Substitute 434 - S for N in (2)

$4S +6(434 - S) = 2032$

Open Bracket

$4S + 2604 - 6S = 2032$

Collect Like Terms

$4S - 6S = 2032 - 2604$

$-2S = -572$

Divide through by -2

$S = 286$

Hence; 286 students attended

Solving (b):

Recall that

$N = 434 - S$

$N = 434 - 286$

$N = 148$

148 non students attended

4 0

2 years ago

Anybody knows all of them?

iragen [17]

Answer:

A, B, C, F, G

Step-by-step explanation:

The above-listed properties are inherited from a parallelogram. The properties not inherited from a parallelogram are ...

D (diagonals are angle bisectors) is inherited from a rhombus

E (congruent diagonals) is inherited from a rectangle

H (perpendicular diagonals) is inherited from a rhombus

7 0

2 years ago

College precalc! Please help! I've been struggling.

kiruha [24]

Answer:

B) f(x) = x if x ≤ -2

2 if x > -2

Step-by-step explanation:

B) f(x) = x if x ≤ -2 (The x and y coordinate have the same value)

2 if x > -2

8 0

3 years ago

Suppose we are testing people to see if the rate of use of seat belts has changed from a previous value of 88%. Suppose that in

Andreas93 [3]

Answer:

a) We would expect to see 500*0.88=440

b) $z=\frac{0.9 -0.88}{\sqrt{\frac{0.88(1-0.88)}{500}}}=1.376$

$p_v =2*P(Z>1.376)=0.167$

So the p value obtained was a very high value and using the significance level assumed $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the true proportion is not significant different from 0.9.

The p value is a criterion to decide if we reject or not the null hypothesis, when $p_v$ we reject the null hypothesis in other case we FAIL to reject the null hypothesis. And represent the "probability of obtaining the observed results of a test, assuming that the null hypothesis is correct".

Step-by-step explanation:

Data given and notation

n=500 represent the random sample taken

X=450 represent the people that have the seat belt fastened

$\hat p=\frac{450}{500}=0.9$ estimated proportion of people that have the seat belt fastened

$p_o=0.88$ is the value that we want to test

$\alpha$ represent the significance level

z would represent the statistic (variable of interest)

$p_v{/tex} represent the p value (variable of interest) Part aWe would expect to see 500*0.88=440Part bConcepts and formulas to use We need to conduct a hypothesis in order to test the claim that the true proportion changes fro m 0.88.: Null hypothesis:[tex]p=0.88$

Alternative hypothesis: $p \neq 0.88$

When we conduct a proportion test we need to use the z statisitc, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.9 -0.88}{\sqrt{\frac{0.88(1-0.88)}{500}}}=1.376$

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level assumed is $\alpha=0.05$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(Z>1.376)=0.167$

So the p value obtained was a very high value and using the significance level assumed $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the true proportion is not significant different from 0.9.

The p value is a criterion to decide if we reject or not the null hypothesis, when $p_v$ we reject the null hypothesis in other case we FAIL to reject the null hypothesis. And represent the "probability of obtaining the observed results of a test, assuming that the null hypothesis is correct".

8 0

2 years ago