Find the point of intersection of y equals x2-6x plus 11 and the lines y equals x and y equals 2x?
y = x^2 - 6x + 11
x + y = 2x
x + y = 2x
x - x + y = 2x - x
y = x
Substitute x for y in the first equation:
y = x^2 - 6x + 11
x = x^2 - 6x + 11
x - x = x^2 - 6x - x + 1
0 = x^2 - 7x + 11
x = [-(-7) ± √[(-7)^2 - 4(1)(11)]]/(2)(1)
x = (7 ± √5)/2
x = (7 + √5)/2 or x = (7 - √5)/2
x ≈ 4.618 or x ≈ 2.382
Since y = x, then y ≈ 4.618 or y ≈ 2.382.
Thus, we can say that the solution of the system are (2.382, 2.382) and (4.618, 4.618).
Why it is necessary for a function to be one-one for existing its inverse?
If it is not 1-1 then you will not know where the inverse value is to be mapped.
For example,
f(x) = x2 , being an even function, is not 1-to-1.
Thus, for example, (-3)2 =9 = 32
Suppose g(x) were the inverse of f(x). What would g(9) be? -3 or 3? There is no way of telling.
The only way around it is to define the domain of x to be non-negative numbers and then f would be 1-to-1 so that g was a well-defined function whose range was the non-negative numbers.
Incidentally, the domain of f could just as well be defined as the non-positive numbers.
Which method would you use to solve this equation5x plus 3y equals 10?
There are an infinite number of solutions to a single equation in two variables.
So, in order to save myself time, the first thing I would do is go out and look for
another equation to put along with the first one.
Yes, because you can rewrite it as:
y = -x/10
Which is a line.
When you graph the above equation, the graph passes the vertical line test - meaning that the graph never intersects with any vertical line more than once.
What property is x plus 3 equals 5 then 2 plus 3 equals 5?
Well, if x+3=5 and 2+3=5, I'm guessing x should equal 2
What is the answer to -2x plus y equals 5?
The answer is any pair of numbers, just as long as the 'y'-number is
5 more than double the 'x'-number. There are an infinite number of them.
You miight think that if there are that many, then it's pretty easy to stumble across
a pair of numbers that's an answer. Unfortunately, there's a bigger infinity of pairs
of numbers that are not answers.
How many gallons of water are contained in a volume of 22 acre-feet?
22 acre-feet equates to 7,169,000 gallons of water.
When do you say that the graph is a function?
A function takes one input and assigns to it exactly one output, so a graph qualifies as a function if it passes the vertical line test (run a vertical line across the entire plane; the function should only cross your line once no matter where you are testing).
What is the answer to 3x2-6x-7 equals 0 in quadratic form?
I would not even attempt to factor this, so the quadratic formula.
X = - b (+/-) sqrt(b2 - 4ac)/2a
a = 3
b = - 6
c = - 7
X = - (- 6 ) (+/-) sqrt[(- 6)2 - 4(3)(- 7)]/2(3)
X = 6 (+/-) sqrt(36 + 84)/6
X = 6 (+/-) sqrt(120)/6
X = 6 (+/-) sqrt( 22 * 30)/6
X = [6 (+/-) 2sqrt(30)]/6
----------------------------------------exact answer less clean up
How do you solve the equation x plus 6 equals x plus 8?
X + 6 = X + 8
This is a nice example of an equation that has no solution.
If you subtract 'X' from both sides of the "equation", it says: " 6 = 8 " .
This should immediately lead us to suspect that something here is not kosher, (that is to say, unorthodox).
What is x if x plus 10 percent of x equals 9705.22?
10 percent = 0.1
'x' plus 10 percent of 'x' = 1.1x
1.1x = 9,705.22
x = 9,705.22/1.1 = 8,822.927 (rounded)
There cannot be a polygon with 6 diagonals.
A polygon with n vertices has n*(n-3)/2 diagonals.
If this is 6, then n*(n-3)/2 = 6
therefore n*(n-3) = 12
and so n^2 - 3n - 12 = 0
The only solutions to this equation are n = 1.5-sqrt(57)/2 or 1.5+sqrt(57)/2.
However, n, being the NUMBER of vertices cannot be an irrational number and so there is no solution.
3x - y equals 3 y equals 2x plus 2?
3x-y = 3y
3x = 4y
y = 0.75x
3x-0.75x = 2x+2
2.25x = 2x+2
0.25x = 2
x = 8
y = 6