The domain are all valid values for x (the independent variable) that can be used in an equation.
We have to look at any potential values of x which won't work. Easily put: in algebra, just look for values of x which cause either division by zero, or the square root of negative numbers.
A couple of examples:
y=2x+4
You can insert any negative or positive value, or zero, for x and get a valid equation. Therefore the domain is the set of all real numbers. Answers are usually written as:
x: {R}, or simply 'all real numbers'.
what about y=2/(x-1)
In this equation, x appears in the denominator. If x-1=0, then division by zero would occur.
Solve: x-1≠0
x≠1
In set notation:
x: (-∞,1)∪(1,∞)
Parentheses are next to the 1, as the domain comes up to 1, but does not include 1.
Read left to right, the domain is "negative infinity to 1, exclusive, in union with 1 to positive infinity"
Answer:
x = 4/3
y = 1/3
Step-by-step explanation:
System of equations! This is set up really well to make the second equation equal x then substitute.
x - y = 1
x = 1 + y
and then our substitution:
2 (1+y) + y = 3
and solve:
2 + 2y + y = 3
3y + 2 = 3
3y = 1
y = 1/3
And now we can substitute that value into one of our equations:
x - (1/3) = 1
x = 4/3
Next we should check by substituting these values into both of our equations:
2 (4/3) + (1/3) = 3
9 / 3 does equal 3 !
(4/3) - (1/3) does equal 1 !
Therefore, x = 4/3 , and y = 1/3
Answer:
The center is (20, 0.05) radius = 9
Step-by-step explanation:
The center is (20, 0.05) radius = 9
from the general form of the equation:
(x - h)^2 + (y - k)^2 = r^2
we see that r^2 = 81
so r = 9
Newton is 762 Km east of Mayfield.
I send you a file wich the answer.
