Answer:
x = 31/35
, y = 8/5
Step-by-step explanation:
Solve the following system:
{7 x - 2 y = 3
14 x + y = 14
Hint: | Choose an equation and a variable to solve for.
In the second equation, look to solve for y:
{7 x - 2 y = 3
14 x + y = 14
Hint: | Solve for y.
Subtract 14 x from both sides:
{7 x - 2 y = 3
y = 14 - 14 x
Hint: | Perform a substitution.
Substitute y = 14 - 14 x into the first equation:
{7 x - 2 (14 - 14 x) = 3
y = 14 - 14 x
Hint: | Expand the left hand side of the equation 7 x - 2 (14 - 14 x) = 3.
7 x - 2 (14 - 14 x) = (28 x - 28) + 7 x = 35 x - 28:
{35 x - 28 = 3
y = 14 - 14 x
Hint: | Choose an equation and a variable to solve for.
In the first equation, look to solve for x:
{35 x - 28 = 3
y = 14 - 14 x
Hint: | Isolate terms with x to the left hand side.
Add 28 to both sides:
{35 x = 31
y = 14 - 14 x
Hint: | Solve for x.
Divide both sides by 35:
{x = 31/35
y = 14 - 14 x
Hint: | Perform a back substitution.
Substitute x = 31/35 into the second equation:
Answer: {x = 31/35
, y = 8/5
9^3= 729, 729 x 4=2916, 2916/3=972, 972 x 3.14 =3052.08
Answer:
y = -3
Step-by-step explanation:
move 2y to the left by subtracting it with 4y
next subtract 6 from both sides
then divide each term by 2
Answer:
Sum of the sequence will be 648
Step-by-step explanation:
The given sequence is representing an arithmetic sequence.
Because every successive term of the sequence is having a common difference d = -3 - (-9) = -3 + 9 = 6
3 - (-3) = 3 + 3 = 6
Since last term of the sequence is 81
Therefore, by the explicit formula of an arithmetic sequence we can find the number of terms of this sequence

where a = first term of the sequence
d = common difference
n = number of terms
81 = -9 + 6(n - 1)
81 + 9 = 6(n - 1)
n - 1 = 
n = 15 + 1 = 16
Now we know sum of an arithmetic sequence is represented by

Now we have to find the sum of the given sequence
![S_{16}=\frac{16}{2}[-9 + (16-1)6]](https://tex.z-dn.net/?f=S_%7B16%7D%3D%5Cfrac%7B16%7D%7B2%7D%5B-9%20%2B%20%2816-1%296%5D)
= 8[-9 + 90]
= 8×81
= 648
Therefore, sum of the terms of the given sequence will be 648.
Answer:
x=3i√6
Step-by-step explanation: