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
Lelechka [254]
2 years ago
8

A system of equations is shown below.

Mathematics
1 answer:
katrin [286]2 years ago
4 0

Answer:

I: 4x-5y=-10

II: 2x-7y=4

c) multiply the second equation by -2 and add the result to the first equation

II*-2=-4x+14y=-8

add I+II*-2: 4x-5y+(-4x+14y)=-10-8

=9y=-18

Step-by-step explanation:

You might be interested in
EMERGENCY!!! OK SO I need help on 4 questions! Lots of points for this :) Also please make sure it's correct cause this is for a
Shalnov [3]

                               <em><u>Question # 1 Solution</u></em>

<em>Answer:</em>

32≤x≤48 is the best estimate for the amount of money, x, that Erika has to pay to get to her destination. Hence, option D is correct.

<em>Step-by-step Explanation:</em>

<em>Information Fetching and Solution Steps</em>

  • Erika estimates that she is 200 to 300 miles away from her destination
  • Car travels 25 miles per gallon of gas
  • Cost of each gallon being $4.00

As Erika estimates that she is 200 to 300 miles away from her destination, and car travels 25 miles per gallon of gas. So,

  • First dividing 200 by 25 to get the number of gallons a car needed to make 200 miles

        i.e 200/25 = 8 gallons.

        As cost of each gallon being $4.00.

        So, 8 × 4 = 32$ is the amount she needed to make 200 miles.

  • Then dividing 300 by 25 to get the number of gallons a car needed to make 300 miles

        i.e 300/25 = 12 gallons.

        As cost of each gallon being $4.00.

        So, 12 × 4 = 48$ is the amount she needed to make 300 miles.

From the above calculation, we observe that 32$ and 48$ is the best estimate between 200 miles and 300 miles.

Therefore, 32≤x≤48 is the best estimate for the amount of money, x, that Erika has to pay to get to her destination. Hence, <em>option D</em> is correct.

<em><u /></em>

<em>                                    </em><u><em>Question # 2 Solution</em></u>

<em>Answer:</em>

<em>Consultant B</em> offers the <em>cheapest price</em> for a <em>five hour session.</em>

Hence, <em>B. Consultant B</em> is the correct option.

<em>Step-by-step Explanation:</em>

<em>Analyzing the offer price of Consultant A, B and C for a Five hour session:</em>

<em />

  • Consultant A chargers $160 for the first hour
  • $75 per hour after the first.

So, for five hour session, Consultant A is offering the price:

$160 + $75 + $75 + $75 + $75 = $460

<em />

  • Consultant B chargers a flat rate of $90 per hour

So, for five hour session, Consultant B is offering the price:

$90 + $90 + $90 + $90 + $90 = 450 US$

<em />

  • Consultant C chargers $140 for the first hour
  • $80 per hour after the first.

So, for five hour session, Consultant C is offering the price:

$140 + $80 + $80 + $80 + $80 = $460

<em>Comparing the price offers of Consultant A, B and C</em>

So, by comparing the price offers of Consultant A, B and C, we determine that:

  • Consultant A is offering the price $460 for five hour session.
  • Consultant B is offering the price $450 for five hour session.
  • Consultant C is offering the price $460 for five hour session.

So, from this comparison, we conclude that <em>Consultant B</em> offers the <em>cheapest price</em> for a <em>five hour session.</em>

Hence, <em>B. Consultant B</em> is the correct option.

<em>                               </em>

<em>                              Question # 3 Solution</em>

<em>Answer:</em>

<em>They spent </em><em>4 nights</em><em> at the hotel. Hence, </em><em>option B</em><em> is correct.</em><em> </em>

<em>Step-by-step Explanation:</em>

<em>To determine: </em>

how many nights did they stay at the hotel?

<em>Information Fetching and Solution Steps</em>

  • A hotel chargers $225 per night to rent a suite.
  • The hotel also charges $75 per day for full room service.
  • Jessica and Ashely purchased full room service for every night.
  • They stayed at the hotel and spent a total of $1,200

As the total amount they spent = $1,200

As $75 is the service charges as Jessica and Ashely purchased full room service for every night.

Per night charges = hotel chargers + service charges

Per night charges = $225 + $75 ⇒ $300

So, total nights will be calculated as:

Total nights = total amount they spent ÷ Per night charges

Total nights = $1,200 ÷ $300 ⇒ 4 nights

<em>Therefore, they spent </em><em>4 nights</em><em> at the hotel. Hence, </em><em>option B</em><em> is correct.</em><em> </em>

<em />

<em>                                  Question # 4 Solution</em>

<em>Answer:</em>

Hence, |h − 57.5| ≤ 7.5 is the absolute values which best represents this restriction, where ( h ) represents height. Hence, <em>option A</em><em> is correct.</em><em> </em>

<em>Information Fetching and Solution Steps</em>

  • A certain ride at an amusement park requires that children be at least 50 inches tall but no more that 65 inches tall.

Let us take the equation of following absolute value:

|h − 57.5| ≤ 7.5

We know h − 57.5 ≤ and h − 57.5 ≥ −50

h − 57.5 ≤ 7.5         (Condition 1)

h − 57.5 + 57.5 ≤ 7.5 + 57.5      (Add 57.5 to both sides)

h ≤ 65

h − 57.5 ≥ −7.5         (Condition 2)

h − 57.5 + 57.5 ≥ −7.5 + 57.5     (Add 57.5 to both sides)

h ≥ 50

So, h ≤ 65 and h ≥ 50

Solution Graph is also attached as shown in attached figure a.

Hence, |h − 57.5| ≤ 7.5 is the absolute values which best represents this restriction, where ( h ) represents height. Hence, <em>option A</em><em> is correct.</em>

<em>Using same methodology we observe that all other options B, C, and D brings </em><em>wrong values </em><em>which is as follows:</em>

  • <em>|h+7.5|≤65 brings h≤57.5 and h≥−72.5</em>
  • <em>|h+50|≤65 brings h≤15 and h≥−115</em>
  • <em>|h+65|≤50 brings h≤−15 and h≥−115</em>

Hence, from all discussion, we conclude that |h − 57.5| ≤ 7.5 is the absolute values which best represents this restriction, where ( h ) represents height, as it brings h ≤ 65 and h ≥ 50. Hence, <em>option A</em><em> is correct.</em>

Keywords: inequality, graph solution, absolute value

Learn more about inequality from brainly.com/question/11315582

Learn more about absolute value from brainly.com/question/2155076

#learnwithBrainly

4 0
3 years ago
Which of the following is the lowest common denominator for the fractions 5/6 and 3/4? A)4 B)12 C)15 D)24
Ksju [112]
It would be 12 the answer
8 0
3 years ago
Evaluate 2b + c<br> for b = 5 and c = 5<br> Please help
Svet_ta [14]

Answer:

2(5)+5=15

Step-by-step explanation:

1. you have the equation 2b+c

2. then you add the numbers for c and b

3. so b=5 and c=5

4. once you add it into the problem then you get 2(5)+5 make sure you remember to times 2 x 5

5. then you do PEMDAS

6. you do multiply so 2x5 is 10

7. then do 10+5 and you get 15 as your answer.

7 0
3 years ago
Determine if each statement is always, sometimes, or never true.
Iteru [2.4K]

Answer:

1) Parallel lines are "ALWAYS"

coplanar.

2) Perpendicular lines ARE "ALWAYS"

coplanar.

3) Distance around an unmarked circle CAN "NEVER" be measured

Step-by-step explanation:

1) Coplanar means lines that lie in the same plane. Now, for a line to be parallel to another line, it must lie in the same plane as the other line otherwise it is no longer a parallel line. Thus, parallel lines are always Coplanar.

2) similar to point 1 above, perpendicular lines are Coplanar. This is because perpendicular lines intersect each other at right angles and it means they must exist in the same plane for that to happen. Thus, they are always Coplanar.

3) to have the distance, we need to have the circle marked out. Because it is from the marked out circle that we can measure radius, diameter and find other distances around the circle. Thus, distance around an unmarked circle can never be measured.

8 0
3 years ago
Someone please help me out:(
gogolik [260]
SAS mmmmmmmmmmmmmmmmmmm
5 0
3 years ago
Other questions:
  • Describe how to solve x^5-2x^3+x=0
    13·1 answer
  • Is 100in more than 3yd 1 ft
    15·2 answers
  • Each bag of birdseed holds 36 cups. Amy feeds the parakeets at a pet shop 4 cups each day. If b represents the number of bags us
    14·1 answer
  • What is a negative plus a negative
    10·2 answers
  • Can someone explain I’m confused on how to do this my teacher can’t teach me this has no time
    7·2 answers
  • Can someone please help me ASAP
    11·2 answers
  • Select the correct answer from each drop menu. A functions with the domain {2,3,4} has a specific range. Determine the function
    6·1 answer
  • if one lottery player A wins the jackpot by matching all five distinct numbers drawn in any order from the white balls (1-42) an
    11·1 answer
  • 1/3(9x + 12) = 15<br> a. x=5<br> b. x=3.67<br> c. x=2.8<br> d. x=4.5
    13·2 answers
  • You get a $60,000 loan for a new dump truck. With the truck, you can generate $500 more business each week at 80% margin. Your i
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!