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3 years ago

If x=2k + 1, y=k - 1 is a solution of the equation 2x - 3y + 5=0. find the value of k.

Mathematics

2 answers:

Ivenika [448]3 years ago

8 0

Value of k is -12.....

Merry Christmas

devlian [24]3 years ago

7 0

Answer:

$x = 2k + 1 \\ y = k - 1 \\ given$

if u substitute the givens in the eqn we will get..

$2(2k + 1) - 2(k - 1) + 5 = 0 \\ 4k + 2 - (2k - 2) + 5 = 0 \\ 4k + 2 - 2k + 2 + 5 = 0 \\$

then collect like terms

$4k - 2k + 2 + 2 + 5 = 0 \\ 2k + 4 + 5 = 0 \\ 2k + 9 = 0$

$2k = - 9 \\ k = \frac{ - 9}{2}$

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Sonia bought $25 concert tickets online, and paid a total of $269. To purchase the tickets there was a service fee of $17. How m

Lelu [443]

Answer: This question is confusing because I can't come up with a whole answer because I don't see a way to get to it no matter how many different ways I try to solve it ;-; The closest I got was $267 with 10 tickets and the fee

Step-by-step explanation:

7 0

3 years ago

Two more than the square of a number is 123 what is the number? Can someone please explain to me how to do this

max2010maxim [7]

Give the number a label. That can be anything you want. A lot of people will use 'x' every single time they do a math problem,but there's no reason to do that and it's boring. Let's call our number ' M ' for 'Mystery number'. OK ?

The number . . . M
The square of the number . . . M²
Two more than the square of the number . . . M² + 2

You said that this is equal to 123, so we can write  M² + 2 = 123

That's the equation we have to take and solve for ' M '.

Subtract 2 from each side of the equation, and you have M² = 121 .

Take the square root of each side: M = √121 .

The Mystery number is the square root of 121.

If you don't happen to know what that is, then you can use your pocket
calculator, or the calculator that comes with your computer (if you know
how to find it). They will all tell you that the square root of 121 is 11 .

That's a fine and wonderful answer, but technically, it's only half of the
answer. Any equation that has something squared in it almost always
has two solutions, and this one does.

The square root of 121 is a number that gives you 121 when you
multiply it by itself. ' 11 ' does that: (11 x 11) = 121 . Is there another
number that does the same thing ?

How about ' -11 ' ? Look at this: ( -11 x -11 ) = 121 . (Remember that
if both numbers being multiplied have the same sign, then their product
is positive.)

The bottom line is: The mystery number is +11 and also -11 .
Either one does what you want . . . When you square it and then
add 2 more, you get 123 either way.

6 0

3 years ago

Mean, Median, Mode and Range. Easy hard math. Please show work and give answers . Need help appreciate you all

tigry1 [53]

Answer:

Step-by-step explanation:

quiz scores:

a. arrange them all from least to greatest to figure out the median first

your quiz: 15, 16, 17, 18, 19 middle # = 17 median = 17

friend's quiz: 12, 13, 17, 20, 20 middle # = 17 median = 17

now for mean add all of your quiz scores up and divide by how many #s

15 + 16 + 17 + 18 + 19 = 85 / 5 = 17 mean = 17

now your friend's:

12 + 13 + 17 + 20 + 20 = 82 / 5 = 16.4 mean = 16.4

mode is which number is used the most

your mode = you don't have a mode your friend's mode = 20

b. you have a higher mean than your friend

world populations:

a. range is to subtract the smallest number from the largest

803 - 31 = 772

b. mean is adding it all up and dividing by how many numbers there are:

803 + 487 + 348 + 368 + 730 + 31 = 2767 / 6 = 461.17

median is arranging them in order and finding the middle #

31, 348, 368, 487, 730, 803

368 + 487 = 855 / 2 = 427.5

mean = 461.17

median = 427.5

mode = no mode

tomato plants:

a. range is subtracting the smallest from the largest

52 - 36 = 16

b. mean is adding all the #s and dividing by how many #s there are:

36 + 45 + 52 + 40 + 38 +41 + 50 + 48 = 350 / 8 = 43.75

median is the middle from least to greatest

36, 38, 40, 41, 45, 48, 50, 52

41 + 45 = 86 / 2 = 43

mean = 43.75

median = 43

mode = no mode

hope this helps! :)

4 0

3 years ago

Find the GCF of 28c-12

stira [4]

THE GCF IS 4; I hope this helps

5 0

3 years ago

Read 2 more answers

Identify the property that justifies "x=y; if y=9, then x=9"

iragen [17]

I think the answer is substitution property of equality because you are substituting 9 for y as y=9.

3 0

3 years ago

If x=2k + 1, y=k - 1 is a solution of the equation 2x - 3y + 5=0. find the value of k.​

If x=2k + 1, y=k - 1 is a solution of the equation 2x - 3y + 5=0. find the value of k.