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
f(x) is a function of x. To find f(-2), plug in the value of x=-2.

The answer is -2.
Answer:
Sample mean weight = 808080 grams
Step-by-step explanation:
The number of samples, n = 161616
The mean weight, 
Standard deviation, 
The sample mean weight,
= Mean weight, 
Since 
Sample mean weight, 
At most, 20. 20 is the greatest common factor of all numbers.
Answer:
45
Step-by-step explanation:
If a(1) = 5, then a(2) = a(1)*3, or 5*3, or 15.
If a(2) = 15, then a(3) = a(2)*3, or a(3) = 15*3 = 45
This is a geometric sequence with first term a(1) = 5 and common ratio 3. We can immediately write the explicit formula
a(n) = 5*3^(n - 1), which correctly predicts that a(3) = 5*3^(3 - 1) = 5*9 = 45