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3 years ago

Use the substitution method to solve the system of equations

Mathematics

1 answer:

PilotLPTM [1.2K]3 years ago

3 0

You solve the substitution method to solve a system of equality by expressing one variable in terms of the other using one equation, and then plugging this expression in the other(s).

In this case, the first equation gives us a way to express n in terms of m. So, we can replace every occurrence of n in the second equation with the given formula.

The result is

$14m+2n=-8 \iff 14m+2(-7m-4)=-8 \iff 14m-14m-8=-8 \iff -8=-8$

So, the second equation turned to be an equality, i.e. an equation where both sides are the same.

This implies that the system has infinitely many solutions, because every couple $(n,m)$ such that $n=-7m-4$ is a solution to the system, because it satisfies both equations: the first is trivially satisfied, whereas the second is an identity, and as such is satisfied by any value of the variable.

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#1 2x-16<-18

Evgesh-ka [11]

Answer:

if it's finding x

#1 x<-1

#2 x<4

Step-by-step explanation:

2x-16<-18

add 16 to both sides

2x<-2

then divide 2 to both sides

x<-1

2x-16+4x<8

add like terms

6x-16+<8

add sixteen to both sides

6x<24

divide six to both sides

x<4

5 0

4 years ago

At the beach, 11% of people have white towels and 53% have blue towels. If

telo118 [61]

Answer:

36 percent.

Step-by-step explanation:

We have been given that 11 percent of people of the peach have white towels, and 53 percent have blue towels.

With this information, we can find the remaining percentage of people that have red towels.

Recall that the total percentage is always 100 percent.

lets make r for the percentage of people that have red towels.

You can solve it by changing it to fraction, decimal, or just keep it at percent.

I will show you all of the possible ways.

Percent:

11 percent plus 53 percent plus r =100 percent

combine the like terms, or add 11 plus 53 to simplify the equation.

You have 64 percent plus r =100 percent Our goal is to isolate r, so subtract both sides by 64 percent.

100-64 is 36 percent.

r=36 percent of people who have red towels.

With fractions.

Write it as 11/100 plus 53/100 plus r/100= 100/100.

Combine the fractions.

64/100 plus r/100=100/100.

Subtract both sides by 64/100.

You are left with r=36/100, 9/25, or 36 percent.

With decimals.

11 percent as a decimal is 0.11. Just move the decimal spot 2 times. In 11, since you can write it as 11.0, you move it to the right twice.

53 percent is 0.53.

r is r.

100 percent is 1.

0.11 plus 0.53 plus r=100

Combine or add 0.53 and 0.11. That is 0.64.

Subtract both sides by 0.64.

You get r to be 0.36 or 36 percent.

I hope this helps, and I hope you have a good day!

8 0

3 years ago

Read 2 more answers

A CBS News/New York Times opinion poll asked 1,190 adults whether they would prefer balancing the federal budget over cutting ta

nikklg [1K]

Using the normal distribution and the central limit theorem, it is found that there is a 0.0166 = 1.66% probability of a sample proportion of 0.59 or less.

In a normal distribution with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

It measures how many standard deviations the measure is from the mean.

After finding the z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X.

By the Central Limit Theorem, the sampling distribution of sampling proportions of a proportion p in a sample of size n has mean $\mu = p$ and standard error $s = \sqrt{\frac{p(1 - p)}{n}}$