1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
crimeas [40]
3 years ago
13

Breann solved the system of equations below. What mistake did she make in her work? 2x + y = 5 x − 2y = 10 y = 5 − 2x x − 2(5 −

2x) = 10 x − 10 + 4x = 10 5x − 10 = 10 5x = 20 x = 4 2(4) + y = 5 y = −3 (5 points) Select one: a. She should have substituted 5 + 2x b. She combined like terms incorrectly, it should have been 4x instead of 5x c. She subtracted 10 from both sides instead of adding 10 to both sides d. She made no mistake
Mathematics
1 answer:
goldfiish [28.3K]3 years ago
5 0

Answer:

No mistake

Step-by-step explanation:

2x + y = 5

x - 2y = 10

y = 5 - 2x

x - 2(5 - 2x) = 10

x - 10 + 4x = 10

5x - 10 = 10

5x = 20

x = 4

2(4) + y = 5

y =  -3

She made no mistake

You can check by plugging in x = 4 and y = -3 into the original equations . They fit exactly.


You might be interested in
Can i get some help and a good explenation
denis-greek [22]

Answer:

The correct answer is $2,50

Step-by-step explanation:

The unit rate is what we use to determine the price of a single unit, when something is sold in a group, as in this case 5 ounces.

4 0
3 years ago
Read 2 more answers
The time taken to assemble a laptop computer in a certain plant is a random variable having a normal distribution of 20 hours an
ludmilkaskok [199]

Answer:

a) 40.13% probability that a laptop computer can be assembled at this plant in a period of time of less than 19.5 hours.

b) 34.13% probability that a laptop computer can be assembled at this plant in a period of time between 20 hours and 22 hours.

Step-by-step explanation:

When the distribution is normal, we use 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 question:

\mu = 20, \sigma = 2

a)Less than 19.5 hours?

This is the pvalue of Z when X = 19.5. So

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

Z = \frac{19.5 - 20}{2}

Z = -0.25

Z = -0.25 has a pvalue of 0.4013.

40.13% probability that a laptop computer can be assembled at this plant in a period of time of less than 19.5 hours.

b)Between 20 hours and 22 hours?

This is the pvalue of Z when X = 22 subtracted by the pvalue of Z when X = 20. So

X = 22

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

Z = \frac{22 - 20}{2}

Z = 1

Z = 1 has a pvalue of 0.8413

X = 20

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

Z = \frac{20 - 20}{2}

Z = 0

Z = 0 has a pvalue of 0.5

0.8413 - 0.5 = 0.3413

34.13% probability that a laptop computer can be assembled at this plant in a period of time between 20 hours and 22 hours.

4 0
3 years ago
Find two consecutive odd integers whose sum is 36.
miskamm [114]
2 consecutive odd integers...x and x + 2

x + (x + 2) = 36
2x + 2 = 36 <===
3 0
3 years ago
Read 2 more answers
URGENT!!
Lapatulllka [165]

Answer:

f[g(4)] = 4

Step-by-step explanation:

Given table:

\begin{array}{| c | c | c | c | c | c |}\cline{1-6} x & -6 & -4 & 1 & 3 & 4\\\cline{1-6} f(x) & 4 & -1 & -6 & 1 & 3 \\\cline{1-6} g(x) & 1 & 4 & 3 & -4 & -6 \\\cline{1-6}\end{array}

f[g(4)] is a composite function.

When calculating <u>composite functions</u>, always work from inside the brackets out.

Begin with g(4):  g(4) is the value of function g(x) when x = 4.

From inspection of the given table, g(4) = -6

Therefore, f[g(4)] = f(-6)

f(-6) is the value of function f(x) when x = -6.

From inspection of the given table, f(-6) = 4

Therefore, f[g(4)] = 4

3 0
2 years ago
Read 2 more answers
You buy a shirt for $25 and sales tax is 4.1
Slav-nsk [51]

Answer:

I think $26.03

Step-by-step explanation:

4.1% of $25 is 1.03 ( I rounded it)

so 1.03 is the sales tax.

$25.00 + $1.03 = 26.03

5 0
3 years ago
Other questions:
  • jordan has a garden that is 528.15 square feet. if she divides the garden into 3 rows of equal size, how many square feet are in
    6·1 answer
  • Which equation or graph represents a non proportional relationship
    15·1 answer
  • Write a function rule relating x and y. x=1,2,3 y=1,8,27.
    12·1 answer
  • Find the product. 4(−12)(−3) A) −144 B) −96 C) 144 D) 72
    9·1 answer
  • I need to solve y=2x-4 solve for y algebraically? That for y
    12·1 answer
  • Se ha preguntado a un grupo de personas jubiladas el número de veces que han ido al teatro en el
    14·1 answer
  • What is the greatest common factor of 55 , 99​
    5·1 answer
  • Help me guysssssssssssssssss :D
    13·2 answers
  • Martin has a pencil case which contains 4 blue pens and 3 green pens. Martin picks a pen at random from the pencil case. He note
    12·2 answers
  • A triangle has an area of 20 in2. If the height
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!