Solve the system of equations by substitution.

3x + y = 9z

-5x + 2y = -4z

What is the value for y from the first equation, that could be substituted into the second equation?

-9z + 3x
3z + 9x
9z - 3x
-3x - 9z

Answers

Answer 1

Answer:

x = 1.27

y = 5.18

Step-by-step explanation:

to solve this system of  equation by simultaneous equation we say that let

3x+y=9.............................. equation 1

-5x+2y=4 .......................... equation 2

from equation 1

3x+y=9.............................. equation 1

y = 9 -3x.............................. equation 3

substitute the value of y = 9 -3x into equation 2

-5x+2y=4 .......................... equation 2

-5x + 2( 9 -3x) = 4

-5x + 18 - 6x = 4

collect the like terms

18 - 4 = 6x + 5x

14 = 11x

divide both side by 11

14/11 = 11x/11

x = 14/11

x = 1.27

put the value of x = 1.27 into  equation 3

y = 9 -3x.............................. equation 3

y = 9 - 3( 1.27)

y = 9 - 3.82

y = 5.18

to check if you are correct put the value of x and y into either equation 1 or equation 2.

3x+y=9.............................. equation 1

3( 1.27) + 5.18 = 9

3.81 + 5.18 = 9

9 = 9


Related Questions

If Store A spend $10,000 more on advertising than store B, then what will be predicted in their sales according to the regression equation?

Answers

Answer:

more sales than b

Step-by-step explanation:

if they invert more in the thing of a company then they will have more ganancia.

answer this question. (5.6)(1.8)

Answers

(5.6)(1.8) the answer is 10.08
10.08 is the answer

Whoever tell me if they had a nice day first I’ll give the brainlyest or however you spell it

Answers

Answer:

hello!

Step-by-step explanation:

i had a nice day i hope you did too :)

A map was made with a scale in which 3 inches represents 450 miles. The actual distance between two cities is 1,350 miles. What is the distance between the same two cities on the map?6 inches

Answers

Answer:

Step-by-step explanation:

(450 miles/3 inches) = 150 miles/inch

(1,250 miles)/(150 miles/inch) = 8.3333 inches

When the actual distance between two cities is 1350 miles the distance between the same cities on the map is 9 inches.

What is proportion?

A mathematical comparison of two numbers is called a proportion. According to proportion, two sets of provided numbers are said to be directly proportional to one another if they increase or decrease in the same ratio.

Given that,

On scale 3 inches represents the actual distance = 450 miles.

To find the distance on scale when actual distance = 1350

Since, 3 inches = 450 miles

1 inch = 450 / 3 = 150 miles

150 miles = 1 inches

1 mile =  / 1/ 150 inches

1350 miles = 1350 / 150 inches = 9 inches

The required distance on scale is 9 inches.

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Can you please help me ASAP!!!
Please help ???
:)


x+8=3x

Answers

Your welcome!

x = 4

Please mark brainiest

The answer will be x = 4, the way to know that is practically move the 8 to the side where is the 3 and convert the positive 8 into a negative 8, then you move the 3 to the other side an change it into a negative 3 to then subtract the 3 with the x and have -2. After that you divide the -2 with the -8 and there is your answer

how do i
factor 7x^2+3x-4

Answers

Answer:

(x+1) (7x - 4)

Step-by-step explanation:

7x² + 3x - 4

Use the diamond...

7 times -4 equals -28 and 7 plus -4 = 3

Use factor by grouping b/c a does not equal 1

7x² + 7x - 4x - 4

7x(x + 1) -4(x + 1)

(x+1) (7x - 4)

what is the value of a in a/5 + 3= 8

Answers

Answer:

Step-by-step explanation:

what is the value of a in a/5 + 3= 8

a/5 + 3= 8

a/5 = 8 - 3

a/5 = 5

a = 5 * 5

a = 25

Answer: a= 25

Step-by-step explanation:

first, you'll have to write the opposite of the + symbol which is - and then you'll have to lose the 3 by substracting it with, so the equation will look like this: a/5= 8-3 not 8+3

a/5=5

after that step you'll have to multiply 5 from the equal sgin with the 5 that is divided by a, so the final equation looks like this:

a=5x5

a=25

now let's make a verification:

25/5+3=8

5+3=8

a=25

hope I helped you :)

Which ordered pair is a solution of the equation?
7x-2y=-57x−2y=−5

Answers

Answer:

what ordered pairs?

Step-by-step explanation:

What is the slope of the line that passes through the points (3, 7), (9, 19) and (5, 11)?

Answers

Answer:

the slope is 2

Step-by-step explanation:

use the slope formula which is y2-y1/x2-x1

A store-bought 400 toys at a cost of ​$10 each. The store sold all the toys at a percent markup of 30%. Find the total selling price.

Answers

Answer:

Step-by-step explanation:

38+105= 143, 39+104=143, and you will find then adding the numbers

List numbers that are between -103 ad -130

Answers

Answer:

104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,124,125, 126, 127, 128, 129

Hello! :)

Numbers between -103 and -130:

-104-105-106-107-108-109-110-111-112-113-114-115-116-117-118-119-120-121-122-123-124-125-126-127-128-129

These are the numbers between -103 and -130. Hope it helps. Please ask if you have any query.

~An excited gal

#CarryOnLearning

[tex]MagicalNature[/tex]

You need to collect at least 32 shells to create a necklace. Your friend gave you 14 and you already had 6. How many more shells do you need to make a necklace? *

Answers

you need 12 more shells

Which is the best reason why 3/5 is the exact quotient for 1/2÷5/6?
3/5 1/2
3/5×1/2=5/6
3/5×5/6=1/2

Answers

Answer:(3/5 times 5/6 = 1/2)

Step-by-step explanation:

Answer:

3/5 x 5/6 = 1/2

Hope it helps

Which statement about liters and milliliters is true?
2) There are 1,000 liters in a milliliter.
» There are 100 milliliters in a liter.
(1) There are 1,000 milliliters in a liter.
There are 100 liters in a milliliter.

Answers

Answer:

There are 1,000 mL in a L

Step-by-step explanation:

All the other answers are wrong

Identify the mistake in the solution below and explain how
to correct it. Determine the correct answer.
Algebra
3x - 5+ 3x = x + 8-x-1
6x – 5 = 2x + 7
4x - 5 = 7
4x = 12
x = 3
Steps
original problem
combine like terms
subtract 2x from both sides
add 5 to both sides
divide both sides by 4
-

Answers

Answer:

Mistake is on second line.

x = 2

Step-by-step explanation:

The first two lines are (I added the boldface):

3x - 5 + 3x = x + 8 - x - 1

6x – 5 = 2x + 7

The first line has x and -x. They add to 0.

The second line on the right side should have just 7, but the x and -x of the first line were incorrectly added together giving 2x.

The second line should be:

6x - 5 = 7

Add 5 to both sides.

6x = 12

Divide both sides by 6.

x = 2

simplify if y<0.

[tex]-\sqrt{9y^{2} }[/tex]

Answers

Answer:

-3y

Step-by-step explanation:

Whether y is smaller than 0 or not, the square root of y^2 is y, a positive quantity.

Thus, -√(9y²) = -3y

Answer

It's actually 3y instead of -3y.

BTW, anybody from RSM

A square carpet covers 75% of the area of the floor.The floor is 8 meters by 8 meters. (a) What are the dimensions of the carpet? (b) What area of the floor is not covered by carpet?

Answers

Answer:

The dimensions of the carpet are 4√3m by 4√3m.

16m² are not covered by the carpet.

Step-by-step explanation:

The area of an 8m by 8m floor is 64m².

[tex]8*8=64[/tex]

A)

First, 75% of that area is 48m².

[tex]64*0.75=48[/tex]

Now we need to find the dimensions of the square carpet. Because it is a square, the length and width have to be the same.

[tex]x*x=48\\x^2=48\\x=\sqrt{48}[/tex]

There's 2 ways to simplify that further as it is not a perfect square. Either just use a calculator to find the root, or factor it out. I won't show how to factor that here as it's not directly relevant, but I can explain it if you're interested.

The 2 solutions are:

[tex]x=6.9282...\\x=4\sqrt{3}[/tex]

The dimensions of the carpet are 4√3m by 4√3m.

B)

Now to find the area that is not covered, just subtract the area that is covered from the total.

[tex]64-48=16[/tex]

16m² are not covered by the carpet.

eight pounds of potatoes is 16 dollars. how much for 5 punds

Answers

Answer: that equals to 1.6

Step-by-step explanation:

(30 Points) A catering company has small tables and large tables. Small tables seat 2 people and large tables seat 5 people. You are planning a party for at most 75 guests. Write an inequality that represents this situation. Let s represent the small tables and I represent the large tables.​

Answers

Answer:

lllllllllllllll

Step-by-step explanation:

its is 15 large tables

Find the slope of each line.

Answers

Answer:

Step-by-step explanation:

There are 4 conditions that have to be met before you can declare what the slope is.

1. y has to be on one side of the equation.

2. y must have a coefficient of +1

3. the other side contains the x value. It can have any number as the slope which is in front of x.  

4. The value of the number by itself which is not connected to x or y can also be  any value including the irrational numbers.

Examples

y = 5x + 4

slope =  5

y intercept = 4

y = πx + sqrt(5)

slope = pi

y intercept = sqrt(5)

Answer to your question

slope = 7/5

y intercept = 5

Jason gets 15 gallons of gas at $3.90 a gallon. 15 gallons gives him 20 miles to the gallon. How many miles can Jason travel on 1 tank of gas?

Answers

He needs one more tank to get one tank of gass because 15 gallons is not enough for one tank. 16 is so, he needs to buy 62.40$

Solve for the unknown side of each right triangle

Answers

x is 9.1 accordingly to the phytagores therom

what is the coordinates of the point? ​

Answers

Answer:

Step-by-step explanation:

3,2

Answer:

2,3 because the point is inside the origin or equivalent so the answer has to be 2,3

Is 8 a unique solution to the equation 3(x-6) =

3x/4

Answers

Answer:

yes

Step-by-step explanation:

3(x - 6) = [tex]\frac{3x}{4}[/tex] ( multiply both sides by 4 to clear the fraction )

12(x - 6) = 3x , distribute left side

12x - 72 = 3x ( subtract 3x from both sides )

9x - 72 = 0 ( add 72 to both sides )

9x = 72 ( divide both sides by 9 )

x = 8

x = 8 is the only solution and is therefore unique

Answer:

8

Step-by-step explanation:

Evaluate the expression for x=2 and y=4


16x0 + 2x2 • y-1

Answers

Answer:

31

Step-by-step explanation

16x0+2x2•y-1

ok now

16•2+2•2•2•4-1

wich is: 31

3 2/7 divided by 1 1/4

Answers

Answer:

92/35

Step-by-step explanation:

⇒ 3 2/7 ÷ 1 1/4

⇒ (3*7 + 2) / 7  ÷ (1*4 + 1) / 4

⇒ 23/7  ÷  5/4

⇒ 23 * 4 /  7 * 5

⇒ 92/35

The solution of the expression is 2 22/35.

What is Division method?

Division method is used to distributing a group of things into equal parts.

Given that;

The expression is,

3 2/7 divided by 1 1/4

Now, Solve the expression as;

3 2/7 ÷ 1 1/4

23/7 ÷ 5/4

23/7 x 4/5

92/35

2 22/35

Hence, The solution of the expression is 2 22/35.

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Multiply as indicated. Write the product in standard form. An explanation is needed.
(2+i)^2

Answers

Answer:

2^2 + i^2  or 4 + i^2 (depending if the teacher wants it simplified or not)

Step-by-step explanation:

(2+i)^2

Basically just add the power to each number using the distributive property. 2 would go to 2^2 (which can be simplified to four) and i would go to i^2.  

What is the distance between the points (-3, 5) and (-3, -6) on the coordinate plane?

Answers

Answer 11
Explanation (x-x) + (y-y)
(0,11) because there is 0 difference in -3 and -3 and a difference of 11 in 5 and -6

Which of the numbers below is greater than 0.75? Select all that apply. A) 32 B) −0.5 C) 1.2 D) −14 E) −2.4

Answers

Answer:

A and B

Step-by-step explanation:

becuz

How to convert minutes and seconds into grades.​

Answers

Answer:

Step-by-step explanation:

To convert time to time, kernel time with 24 (number of time in a day).

To convert time to minutes, kernel with time with 1440 (number of minutes in a day = 24 * 60).

To convert s to seconds, multiply the time by 86400 (number of s in a day = 24 * 60 * 60).

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