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2 years ago

Solving systems of equations using substitution y=7 3x-3y=-18

Mathematics

1 answer:

oksano4ka [1.4K]2 years ago

5 0

Answer:

x = 1

Step-by-step explanation:

If you have any questions feel free to ask in the comments

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Y= -7x-2 y+ 3 = -7x + 1 ( 2,3) no solution an infinite number of solutions

Naya [18.7K]

Answer:

Infinite number of solutions.

Step-by-step explanation:

y = -7x - 2

y + 3 = -7x + 1

Subtract 3 from both sides:

y = -7x - 2

- this is the same as the first equation.

We can put any number of valid combinations of x and y into this equation.

So there are infinite solutions.

8 0

3 years ago

Please help answer this question I’m just stupid

kykrilka [37]

1500
600 per hour

It starts at 1500 and then after one hour
It go up to 2,100 then 2700

8 0

2 years ago

Read 2 more answers

Dont really understand how to do this

bija089 [108]

Answers:

$t_{10} = -22 \ \text{ and } S_{10} = -85$

========================================================

Explanation:

$t_1 = \text{first term} = 5\\t_2 = \text{first term}-3 = t_1 - 3 = 5-3 = 2$

Note we subtract 3 off the previous term (t1) to get the next term (t2). Each new successive term is found this way

$t_3 = t_2 - 3 = 2-3 = -1\\t_4 = t_3 - 3 = -1-3 = -4$

and so on. This process may take a while to reach $t_{10}$

There's a shortcut. The nth term of any arithmetic sequence is

$t_n = t_1+d(n-1)$

We plug in $t_1 = 5 \text{ and } d = -3$ and simplify

$t_n = t_1+d(n-1)\\t_n = 5+(-3)(n-1)\\t_n = 5-3n+3\\t_n = -3n+8$

Then we can plug in various positive whole numbers for n to find the corresponding $t_n$ value. For example, plug in n = 2

$t_n = -3n+8\\t_2 = -3*2+8\\t_2 = -6+8\\t_2 = 2$

which matches with the second term we found earlier. And,

$tn = -3n+8\\t_{10} = -3*10+8\\t_{10} = -30+8\\t_{10} = \boldsymbol{-22} \ \textbf{ is the tenth term}$

---------------------

The notation $S_{10}$ refers to the sum of the first ten terms $t_1, t_2, \ldots, t_9, t_{10}$

We could use either the long way or the shortcut above to find all $t_1$ through $t_{10}$ . Then add those values up. Or we can take this shortcut below.

$Sn = \text{sum of the first n terms of an arithmetic sequence}\\S_n = (n/2)*(t_1+t_n)\\S_{10} = (10/2)*(t_1+t_{10})\\S_{10} = (10/2)*(5-22)\\S_{10} = 5*(-17)\\\boldsymbol{S_{10} = -85}$

The sum of the first ten terms is -85

-----------------------

As a check for $S_{10}$ , here are the first ten terms:

t1 = 5
t2 = 2
t3 = -1
t4 = -4
t5 = -7
t6 = -10
t7 = -13
t8 = -16
t9 = -19
t10 = -22

Then adding said terms gets us...

5 + 2 + (-1) + (-4) + (-7) + (-10) + (-13) + (-16) + (-19) + (-22) = -85

This confirms that $S_{10} = -85$ is correct.

6 0

1 year ago

2m-1-5m+4 what is the answer?

KiRa [710]

$2m-1-5m+4$

$(2m-5m)-1+4

 
$ $Gather \ like \ terms$

$-3m-1+4$

$-3m+3$

8 0

3 years ago

Someone please help me with this!! i really need this to pass :(

DochEvi [55]

Answer:

Option :" Use distance formula to prove that the lengths of the diagonals are equal" is correct

Step-by-step explanation:

Option : Use distance formula to prove that the lengths of the diagonals are equal" is correct.

Because " By using the coordinate geometry to prove that the diagonals of the rectangle are congruent, first we have to find the lengths of the top and bottom of the rectangle and then solve it for the lengths of the diagonals by using the distance formula".

3 0

2 years ago