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2 years ago

If 2x + 5y = 21 and x + y = 3, then what is the solution

Mathematics

1 answer:

Viefleur [7K]2 years ago

8 0

2x+5y=21, x+y=3
y=3-x
2x+5y=21
2x+5(3-x) =21
2x+15-5x=21
2x-5x+15=21
-3x+15=21
-3x=21-15
-x=6/3
-x=2
x=-2

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Symposium is part of a larger work referred to as Plato's Dialogues. Wishart and Leach† found that about 21.4% of five-syllable

notsponge [240]

Complete Question

ymposium is part of a larger work referred to as Plato's Dialogues. Wishart and Leach† found that about 21.4% of five-syllable sequences in Symposium are of the type in which four are short and one is long. Suppose an antiquities store in Athens has a very old manuscript that the owner claims is part of Plato's Dialogues. A random sample of 498 five-syllable sequences from this manuscript showed that 129 were of the type four short and one long. Do the data indicate that the population proportion of this type of five-syllable sequence is higher than that found in Plato's Symposium? Use = 0.01.

a. What is the value of the sample test statistic? (Round your answer to two decimal places.)

b. Find the P-value of the test statistic. (Round your answer to four decimal places.)

Answer:

a) $Z=2.45$

b) $P Value=0.0073$

Step-by-step explanation:

From the question we are told that:

Probability of Wishart and Leach $P=21.4=>0.214$

Population Size $N=498$

Sample size $n=12$

Therefore

$P'=\frac{129}{498}$

$P'=0.2590$

Generally the Null and Alternative Hypothesis is mathematically given by

$H_0:P=0.214$

$H_a:=P>0.214$

Test Statistics

$Z=\frac{P'-P}{\sqrt{\frac{P(1-P)}{n}}}$

$Z=\frac{0.2590-0.214}{\sqrt{\frac{0.214(1-0.214)}{498}}}$

$Z=2.45$

Therefore P Value is given as

$P Value =P(Z\geq 2.45)$

$P Value =1-P(Z\leq 2.45)$

$P Value =1-0.99268525$

$P Value=0.0073$

7 0

2 years ago

I need help 6x-2y=10 x-2y=-5 solve by elimination

dem82 [27]

<h3><u>Explanation</u></h3>

Given the system of equations.

$\begin{cases} 6x - 2y = 10 \\ x - 2y = - 5 \end{cases}$

Solve the system of equations by eliminating either x-term or y-term. We will eliminate the y-term as it is faster to solve the equation.

To eliminate the y-term, we have to multiply the negative in either the first or second equation so we can get rid of the y-term. I will multiply negative in the second equation.

$\begin{cases} 6x - 2y = 10 \\ - x + 2y = 5 \end{cases}$

There as we can get rid of the y-term by adding both equations.

$(6x - x) + ( - 2y + 2y) = 10 + 5 \\ 5x + 0 = 15 \\ 5x = 15 \\ x = \frac{15}{5} \longrightarrow \frac{ \cancel{15}}{ \cancel{5}} = \frac{3}{1} \\ x = 3$

Hence, the value of x is 3. But we are not finished yet because we need to find the value of y as well. Therefore, we substitute the value of x in any given equations. I will substitute the value of x in the second equation.

$x - 2y = - 5 \\ 3 - 2y = - 5 \\ 3 + 5 = 2y \\ 8 = 2y \\ \frac{8}{2} = y \\ y = \frac{8}{2} \longrightarrow \frac{ \cancel{8}}{ \cancel{2}} = \frac{4}{1} \\ y = 4$