Solve the system of equations and choose the correct ordered pair. 3x + 4y = 38 5x - 5y = -30

1 answer:

3 0

3x + 4y = 38 ( equation 1) ----> ×5 5x - 5y = -30 ( equation 2) ----> ×3 When you multiply eqn 1 by 5 you get, 15x + 20y = 190 And when you multiply eqn 2 by 3, you get, 15x - 15y = -90 Then you solve both equations by subtracting eqn 2 from eqn 1 15x + 20y = 190 15x - 15y = 90 Then 15x - 15x gets cancelled and 20y - (-15y) gives 35y and 190 - (-90) gives 280. So that gives 35y = 280 y = 8 And when you replace y = 8 in any of the two equations, x = 2

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The United States Postal Service reports 95% of first-class mail within the same city is delivered within two days of the time o

choli [55]

Answer:

Step-by-step explanation:

This is a binomial probability distribution because the outcome is either a randomly selected first-class mail within the same city is delivered within two days of the time of mailing or more days. The probability of success, p is that it is delivered within 2 days. Therefore,

p = 95/100 = 0.95

q(probability of success) = 1 - p = 1 - 0.95 = 0.05

n = number of samples = 6

1)The probability that all six arrive within two days, P(x = 6) would be determined from the binomial probability distribution calculator. Therefore,

P(x = 6) = 0.74

2) P(x = 5) = 0.23

3) mean = np = 6 × 0.95 = 5.7

4) Variance = npq = 6 × 0.95 × 0.05 = 0.285

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8 0

3 years ago

What are the roots of the equation?<br><br> x^2(6x−11)(7x−8)=0

trasher [3.6K]

multiply all the factors in x^2

to get the roots which are 0, 11/6 and 8/7

3 0

3 years ago

Read 2 more answers

the first term of a arithmetic sequence is 2 and the 4th term is 11, how do I find the sum of the first 50 terms

Rama09 [41]

$\bf n^{th}\textit{ term of an arithmetic sequence}\\\\
a_n=a_1+(n-1)d\qquad 
\begin{cases}
n=n^{th}\ term\\
a_1=\textit{first term's value}\\
d=\textit{common difference}\\
----------\\
a_1=2\\
a_4=11\\
n=4
\end{cases}
\\\\\\
a_4=2+(4-1)d\implies 11=2+(4-1)d\implies 11=2+3d
\\\\\\
9=3d\implies \cfrac{9}{3}=d\implies \boxed{3=d}\\\\
-------------------------------\\\\$

$\bf \textit{now, what's the 50th term anyway?}
\\\\\\
n^{th}\textit{ term of an arithmetic sequence}\\\\
a_n=a_1+(n-1)d\qquad 
\begin{cases}
n=n^{th}\ term\\
a_1=\textit{first term's value}\\
d=\textit{common difference}\\
----------\\
a_1=2\\
n=50\\
d=3
\end{cases}
\\\\\\
a_{50}=2+(50-1)3\implies a_{50}=2+147\implies a_{50}=149\\\\
-------------------------------\\\\$

$\bf \textit{sum of a finite arithmetic sequence}\\\\
S_n=\cfrac{n}{2}(a_1+a_n)\quad 
\begin{cases}
n=50\\
a_1=2\\
a_{50}=149
\end{cases}\implies S_{50}=\cfrac{50}{2}(2+149)$

7 0

4 years ago

The question is below:

Sonbull [250]

<h3>Hello There!!</h3><h2 /><h3><u>Given</u></h3>

$3(x - 2) + 7x = \frac{1}{2} (6x - 2)$

<h3><u>Solving </u><u>It</u></h3>

$3(x - 2) + 7x = \frac{1}{2} (6x - 2) \\ \\ \implies3x - 6 + 7x = ([\frac{1}{2} \times 6 \: x] - [\frac{1}{2} \times 2]) \\ \\ \implies10x - 6 = ([\frac{1}{ \cancel2} \times \cancel 6 \: x] - [\frac{1}{ \cancel2} \times \cancel2]) \\ \\ \implies 10x - 6 = 3x - 1 \\ \\ \fbox{Bringing (3x )to left side whereas( - 6 )in right side} \\ \\ \implies10x - 3x = - 1 + 6 \\ \\ \implies7x = 5 \\ \\ \therefore x = \frac{5}{7}$