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3 years ago

The total bill of a meal at a restaurant is 25x – 115. Five

Mathematics

2 answers:

AlexFokin [52]3 years ago

8 0

Answer:

5x - 23

Step-by-step explanation:

You could divide the whole equation by 5 since there are 5 friends. Once you do that you end with the equation 5x - 23, which is what each friend would pay.

lesantik [10]3 years ago

4 0

Answer: Divide the whole equation by 5

Step-by-step explanation: You could divide the whole equation by 5 since there are 5 friends. Once you do that you end with the equation 5x - 23, which is what each friend would pay.

You might be interested in

If solving a system of linear equations by elimination or substitution I get that 0=0, as final or intermediate step depending o

aniked [119]

Answer:

If I get 0=0 then it means:

If the system of equations is 2 linear equations in 2 variables, there is infinity number of solutions
If the system of equations is 3 linear equations in 3 variables, there might be infinite number of solutions

Step-by-step explanation:

Linear equation systems can consist of two or three equations with two or three unknowns respectively.

A system of linear equations in two variables has infinite solutions when the lines made by them overlap each other and similarly a system with three variables has infinite solutions when two lines overlap each other and third plane is parallel to them

Hence,

If I get 0=0 then it means:

If the system of equations is 2 linear equations in 2 variables, there is infinity number of solutions
If the system of equations is 3 linear equations in 3 variables, there might be infinite number of solutions

4 0

3 years ago

Solve the simultaneous equations

Contact [7]

Answer:

The solution for given system of equations is: x = 6 and y = 3

(6,3)

Step-by-step explanation:

Given equations are:

$3x+4y=30\ \ \ Eqn\ 1\\3x-y=15\ \ \ \ Eqn\ 2$

There are three methods to solve simultaneous equations

Elimination
Substitution
Co-efficient method

We will use the elimination method as the coefficients of x in both equations are already same

Subtracting equation 2 from equation 1

$3x+4y - (3x-y) = 30-15\\3x+4y-3x+y = 15\\5y = 15\\\frac{5y}{5} = \frac{15}{5}\\y = 3$

Putting y = 3 in equation 2

$3x-3 = 15\\3x = 15+3\\3x = 18\\\frac{3x}{3} = \frac{18}{3}\\x = 6$

Hence,

The solution for given system of equations is: x = 6 and y = 3

(6,3)

7 0

3 years ago

A hyperbola centered at the origin has a vertex at (9, 0) and a focus at (−15, 0). Which are the equations of the asymptotes? y

chubhunter [2.5K]

Well, we know is centered at the origing, thus h,k are just 0,0.

using the provided vertex and focus point, gives us a distance for "a" of 9 and a distance for "c" of 15, check the picture below.

$\bf \textit{hyperbolas, horizontal traverse axis }\\\\
\cfrac{(x- h)^2}{ a^2}-\cfrac{(y- k)^2}{ b^2}=1
\qquad 
\begin{cases}
center\ ( h, k)\\
vertices\ ( h\pm a, k)\\
c=\textit{distance from}\\
\qquad \textit{center to foci}\\
\qquad \sqrt{ a ^2+ b ^2}\\
\textit{asymptotes}\quad 
y= k\pm \cfrac{b}{a}(x- h)
\end{cases}\\\\
-------------------------------$

$\bf \begin{cases}
a=9\\
c=15
\end{cases}\implies c=\sqrt{a^2+b^2}\implies \sqrt{c^2-a^2}=b
\\\\\\
\sqrt{15^2-9^2}=b\implies \sqrt{144}=b\implies \boxed{12=b}\\\\
-------------------------------\\\\
asymptotes\qquad y=0\pm\cfrac{12}{9}(x-0)\implies y=\pm\cfrac{4}{3}x$

3 0

4 years ago

Read 2 more answers

Two alloys A and B are being used to manufacture a certain steel product. An experiment needs to be designed to compare the two

sveta [45]

Answer:

Step-by-step explanation:

From the given information, we can compute the table showing the summarized statistics of the two alloys A & B:

Alloy A Alloy B

Sample mean $\bar {x} _A = 49.5$ $\bar {x} _B = 45.5$

Equal standard deviation $\sigma_A = 5$ $\sigma_B= 5$

Sample size $n_A = 30$ $n_{B}= 30$

Mean of the sampling distribution is :

$\mu_{\bar{X_1}-\bar{X_2}}= 49.5-45.5 \\ \\ = 4.0$

Standard deviation of sampling distribution:

$\sigma_{\bar{x_1}-\bar{x_2} }= \sqrt{\sigma^2_{\bar{x_1}-\bar{x_2} }} \\ \\ = \sqrt{\dfrac{\sigma_1^2}{n_1} + \dfrac{\sigma^2_2}{n_2} } \\ \\ =\sqrt{\dfrac{25}{30}+\dfrac{25}{30}} \\\\=\sqrt{1.667} \\ \\ =1.2909$

Hypothesis testing.

Null hypothesis: $H_o: \mu_A -\mu_B = 0$

Alternative hypothesis: $H_A:\mu_A -\mu_B > 4$

The required probability is:

$P(\overline X_A - \overline X_B>4|\mu_A - \mu_B) = P\Big (\dfrac{(\overline X_A - \overline X_B)-\mu_{X_A-X_B}}{\sigma_{\overline x_A -\overline x_B}} > \dfrac{4 - \mu_{X_A-\overline X_B}}{\sigma _{\overline x_A - \overline X_B}} \Big) \\ \\ = P \Big( z > \dfrac{4-0}{1.2909}\Big) \\ \\ = P(z \ge 3.10)\\ \\ = 1 - P(z < 3.10) \\ \\ \text{Using EXCEL Function:} \\ \\ = 1 - [NORMDIST(3.10)] \\ \\ = 1- 0.999032 \\ \\ 0.000968 \\ \\ \simeq 0.0010$

This implies that a minimal chance of probability shows that the difference of 4 is not likely, provided that the two population means are the same.

Since the P-value is very small which is lower than any level of significance.

Then, we reject $H_o$ and conclude that there is enough evidence to fully support alloy A.

3 0

3 years ago

Solve and receive BRAINLIST

stira [4]

-x+4y= -17
-x= -17-4y multiply everything by -1
x=17+4y

-6X-2y=2
-6(17+4y) - 2y=2
-102-24y-2y=2
-26y=2+102
-26y=104
y= -104/26
y= -4

x=17+4y
x=17+4•4
x=17+16
x=33

8 0

3 years ago