A variable needs to be eliminated to solve the system of equation below. Choose the correct first step.

Mathematics

1 answer:

prohojiy [21]2 years ago

4 0

Answer:

−

-21

Step-by-step explanation:

3x−9y=−39, 3x−6y=−21 : x=5, y=6

Steps

[ 3x−9y=−39 3x−6y=−21 ]

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Isolate x for 3x−9y=−39: x=−13+3y

Substitute x=−13+3y

[ 3(−13+3y)−6y=−21 ]

Show Steps

Simplify

[ −39+3y=−21 ]

Show Steps

Isolate y for −39+3y=−21: y=6

For x=−13+3y

Substitute y=6

x=−13+3· 6

Simplify

x=5

The solutions to the system of equations are:

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workers on the simile line produce 4 x + 6 bolts each day which expression shows how many books they produced in 12 days

kakasveta [241]

4x+6 is produced each day.
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7 0

2 years ago

Suppose that birth weights are normally distributed with a mean of 3466 grams and a standard deviation of 546 grams. Babies weig

Anon25 [30]

Answer:

3.84% probability that it has a low birth weight

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

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

The Z-score 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. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 3466, \sigma = 546$