The sum of two numbers is 30. Their difference is 12. Use substitution to solve a system of equations to solve for the two numbers.

Answers

Answer 1

Answer:

9 and 21

Step-by-step explanation:

setting up the equation

let x and y represent the two numbers

this means that x + y = 30

x - y = 12

using substitution to solve

if x - y = 12, that can be rearranged to x = y + 12.

substitute x = y + 12 into x + y = 30

you get (y + 12) + y = 30

simplify

2y + 12 = 30

2y = 18

y = 9

plug this into the original equation x + y = 30. this would be

x + 9 = 30

x = 21

the numbers are 21 and 9.


Related Questions

Put these numbers in order from least to greatest.
1/2 1/10 0.4?

Answers

Answer:

1/10, 0.4, 1/2

Step-by-step explanation:

Answer:

1/10      0.4        1/2

Step-by-step explanation:

1/10 = 0.1

0.4 = 0.4

1/2 = 0.5

therefore 0.1  0.4  0.5

Just list all of the possible answers

Answers

Answer:

what grade are you??........

Answer:

8th idea I'm sorry. uhhhhhhhh just wait not

Gonna be sending in quite a few of these lol thanks

Answers

Answer:

A

Step-by-step explanation:

Simply multiply each rows of the firstly stated matrix by the columns of the second and then add each with respect to their location.

A card is fresh from an ordinary deck. Find the probability that it did a diamond given that it is a jack

Answers

Answer:

1/52

Step-by-step explanation:

A deck has 52 cards and the probability of picking a specific one is 1/52, or 1.92%

If you are looking for the probability of a diamond, it is 1/4, or 25%

Pls help need it right now :((
If the standard deviation of of the values 2,4, 6,8 is 2.236, the the standard deviation of the values 4, 8, 12, 20 is?​

Answers

Answer:

5.916

count N : 4

Sum, Ex : 44

Mean , M

Variance , o2 : 35

Step-by-step explanation:

we are creating the mean value of the squares of the differences of each data point to the mean value (variance), and then we pull the square root to bring the differences back to the same dimension as the basic data points.

and since we are dealing with the whole "population" of data points and not only with a sample of a much larger set of data points, that mean value of the differences is a true mean value (divide by n = the number of data points). if we would deal with a sample of a much larger population, we would divide by n-1.

so, how does this work in practice ?

let's go first for the given example :

2, 4, 6, 8.

the mean value is : (2+4+6+8)/4 = 20/4 = 5.

the variance (mean value of the squared differences of each data point to the mean value) :

((2-5)² + (4-5)² + (6-5)² + (8-5)²)/4 = (9+1+1+9)/4 = 20/4 = 5.

the standard deviation is the square root of the variance.

so,

SD = sqrt(5) = 2.236067977...

now for the given problem :

4, 8, 12, 20

the mean value is : (4+8+12+20)/4 = 44/4 = 11.

the variance (mean value of the squared differences of each data point to the mean value) :

((4-11)² + (8-11)² + (12-11)² + (20-11)²)/4 = (49+9+1+81)/4 = 140/4 = 35.

the standard deviation is the square root of the variance.

so,

SD = sqrt(35) = 5.916079783... ≈ 5.916

can anyone please tell me how to do this​

Answers

Hello there, this problem is just basic addition, here is what it would look like

[tex]52.31+25.90[/tex]

Solve it and we get 78.21

Amount earned on Saturday = $ 52.31

Amount earned on Sunday = $ 25.90

Total amount earned

= $ 52.31 + $ 25.90

= $ 78.21

Therefore, Tara earned $ 78.21 in total. Hope this helps.

Have a nice day.

PLEASE HURRY! WILL MARK BRAINLIEST IF CORRECT!! (Screenshot)

Answers

The correct answer is 6 2/3

I will give brainliest to whoever gets the right answer

Answers

Answer:

[tex]18[/tex]

Step-by-step explanation:

Step 1:  Input the values and solve

[tex]b - 7a[/tex]

[tex](4) - 7(-2)[/tex]

[tex]4 - (-14)[/tex]

[tex]4 + 14[/tex]

[tex]18[/tex]

Answer:  [tex]18[/tex]

HELP

HOW AM I MEANT TO ANSWER THIS QUESTION I WOULD ASO LIKE ANSWER.

THX

Answers

To find the number in a square, we have to multiply two circles which are connected to it.So, to find a number in a circle, we have divide the number in the square by the number in the circle connected to it.Therefore, -6 ÷ -3 = 212 ÷ 2 = 66 × -3 = -18

Please find the attached photograph for their positions.

Hope you could get an idea from here

Doubt clarification - use comment section.

Can someone please help me

Answers

Answer:

all the small nembers x

Step-by-step explanation:

Enter the number that belongs in the green box

Answers

Answer:

8

Step-by-step explanation:

The diagonals of a parallelogram divide each other into two equal parts.

9 + 6 + 5+ 15
Is that

Answers

9+6= 15
15+5=20
20+15=35
35 is the answer.

Enter the number that belongs in the green box

Answers

Answer:

72°

Step-by-step explanation:

The diagonals of a parallelogram intersect at a point that forms the center of symmetry of the parallelogram.

the answer is 72°, since vertical angles are equal to each other.

help asap!!!! please!!

Answers

Answer:

13 blue and 20 yellow

urwelcome

The lengths two sides of a triangle are 10 cm and 11cm. Between what two measures should the length of the third side fall?

Answers

Step-by-step explanation:

a triangle can only be a triangle (all sides connect with each other), if every side is less than the sum of the other 2 sides.

so, the third side must be shorter than 10+11 = 21 and longer than 11-10 = 1, so that the side of 11 cm is shorter than the sum of the other two sides.

Answer:

1 < x < 21

Step-by-step explanation:

Given 2 sides of a triangle then the third side x is in the range

difference of 2 sides < x < sum of 2 sides , that is

11 - 10 < x < 11 + 10

1 < x < 21

Cheyenne is on her school swim team.
She has won 6 of her 15 events so far
this year. Which equation can be used
to determine how many events she will
need to win in a row to have an overall
win rate of 75%?

Answers

The equation that can be used to determine how many events Cheyenne will need to win in a row to have an overall win rate of 75% is x+6=(3/4)×15.

What is an equation?

An equation is formed when two equal expressions are equated together with the help of an equal sign '='.

Given that there is a total of 15 events. And in order to win 75% of the event, Cheyenne need to win,

The number of matches Cheyenne needs to win = 75% of 15

                                                                                 = 11.25 ≈ 12 events

Since Cheyenne has already won 6 events out of 15, she needs to win 6 more events.

Hence, the equation that can be used to determine how many events Cheyenne will need to win in a row to have an overall win rate of 75% is x+6=(3/4)×15.

Learn more about Equation:

https://brainly.com/question/2263981

#SPJ2

At M & P’s Deli, two pastrami sandwiches and five sodas cost $12.65, while three pastrami sandwiches and two sodas also cost $12.65. How many dollars would seven pastrami sandwiches and twelve sodas cost?

Answers

Answer:

37.95

Step-by-step explanation:

MATH

The cost of seven pastrami sandwiches and twelve sodas is $40.08.

What is an expression?

Expression in maths is defined as the collection of the numbers variables and functions by using signs like addition, subtraction, multiplication, and division.

Numbers (constants), variables, operations, functions, brackets, punctuation, and grouping can all be represented by mathematical symbols, which can also be used to indicate the logical syntax's order of operations and other features.

Given that at M & P’s Deli, two pastrami sandwiches and five sodas cost $12.65, while three pastrami sandwiches and two sodas also cost $12.65.

2P + 5S = 12.65

3P + 2S = 12.65

2P + 5S = 3P + 2S

P = 3S

3 x 3S + 2S = 12.65

6S + 2S = 12.65

8S = 12.65

S = $1.58

P = $3.16

The cost of seven pastrami sandwiches and twelve sodas will be:-

Cost = 7P = 12S

Cost = ( 7 x 3.16 ) + ( 1.58 x 12 )

Cost = $41.08

To know more about an expression follow

https://brainly.com/question/29379220

#SPJ6

please help ill mark brainliestO​

Answers

Answer:

8 cm

Step-by-step explanation:

According to the condition,

[tex]\dfrac{PQ}{RS} = \dfrac{QT}{ST}\\\\\implies \dfrac{9}{3} = \dfrac{QT}{4}\\\\ \implies 3 =\dfrac{QT}{4}\\\\\implies QT = 3 \times 4 = 12~ \text{cm}\\\\\text{Hence}~ QS =QT - ST = 12 -4 = 8~ \text{cm}[/tex]

1. Which calculation best matches the expression 3y + 2?
A. 3 times 2, plus y
B. 3 times y, plus 2
C. 3 times the sum ofy and 2
D. 3 times the difference of y and 2

Answers

the answer is "B" (3 times y, plus 2). we know this bc 3y just means 3(y), and then you add 2. we also know can use process of elimination. "A" would be written as 3(2)+y, "C" would be written as 3(y+2), and "D" would be written as 3(y-2). hope this helped :)
The answer is: B - 3 times y, plus 2.

Simplify the expression.
5(2 +t) – 3(t + 1)
please help as soon as possible

Answers

Answer:

7 + 2t is the simplest form of your equation.

Hope this helps! :D

?????????????????????​

Answers

Answer: make me  brainlist

Step-by-step explanation: 13 is A

the one next to it is D so it is D

what are prime factors of 1000?

Answers

Answer:

1,2,4,5,8,10,20,25,40,50,10,125,200,250,500,1000

Step-by-step explanation:

prime factorization is

1000=2*2*2*5*5*5

Solve. 4 + x 7 = 2
pls helpppp

Answers

Answer: x=14

Step-by-step explanation:

4+x/7=2

-4 -4

X/7=-2

*7 *7

X=14

Answer:

-14

Step-by-step explanation:

A dugout needs to reach at least 54 feet below ground level. This means it needs to be more than 214 times its current depth. This depth is represented by the inequality 214d<−54, where d is the current depth of the dugout.

Select from the drop-down to correctly interpret the solution of this inequality.

The current depth of the dugout is
Choose...
feet below ground level.

Answers

Solving the inequality, it is found that:

The current depth of the dugout is of 0.25 feet below ground level.

The current depth of the dugout is of d.

The inequality below represents how much the dugout needs to reach, according to the current depth:

[tex]214d < -54[/tex]

We solve it similarly to an equality, hence:

[tex]d < -\frac{54}{214}[/tex]

[tex]d < -0.25[/tex]

The current depth of the dugout is of 0.25 feet below ground level.

A similar problem is given at https://brainly.com/question/14361489

Answer:

deeper then 24

Step-by-step explanation:

Please make me brainliest

rico wants to buy a battery operated toy car which caused 580 7.50 he has already save one 50.00 points his ninong give him 200 point zero zero if he saved 12.50 a day from his allowance how long will it take him to save the rest of money to buy the toy car​

Answers

Answer:

19 days

Step-by-step explanation:

1 - Make an equation with the variables provided.

150 + 200 + 12.50x = 587.50

2 - Simplify both sides.

350 + 12.50x = 587.50

3 - Subtract 350 from both sides.

12.50x = 237.50

4 - Divide by 12.50 to find your x variable.

x = 19 days

Brainliest would be appreaciated! :-)

Find the slope of the line that passes through (6, 8) and (2, 17).

Simplify your answer and write it as a proper fraction, improper fraction, or integer.

Answers

Answer:

-9/4

Step-by-step explanation:

Slope is equal to the change in y, over the change in x, or rise over run.

x, is the run

y, is the rise

You can substitute the coordinate numbers on the equation to find the slope. which is y2-y1/x2-x1

m= 17-(8)

——

2-(6)

Your answer will be -9/4 (it doesn’t matter where the negative goes, and there’s a negative because 2-6= -4)

Hope this helps.

Pls help is correct ASAP

Answers

yeah, its correct! :)

table devide by 666 multypli by 9999999999999999999999999999999 please help faster 50 seccond remaoning

Answers

Answer:

6.66e+33

Step-by-step explanation:

Is this a real question??

6.66634456433333557883363357883577 according to my Calculator

Help ASAP please. I really need the answer as soon as possible

Answers

Answer:

y intercept is 6 and the rate of change is Y=3x+6

Step-by-step explanation:

Answer:

y intercept = 6

rate of change = -4

Step-by-step explanation:

the line hits the y axis at 6 so that is the y intercept

The line falls 4 and goes over 1

I hope this helps!!

write one equivalent ratio of the given radio

1. 3/9
2.6/7
3.11/12
4.2/8
5.3/6​

Answers

1/3
12/14
22/24
1/4
1/2
hope it helps
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