A irrational number is a number that can't be expressed as a ratio of two whole numbers. That's it.
For examples (in increasing order of difficulty)
1 is a rational number because it is 1/1
0.75 is a rational number because it is equal to 3/4
2.333... (infinite number of digits, all equal to three) is rational because it is equal to 7/3.
sqrt(2) is not a rational number. This is not completely trivial to show but there are some relatively simple proofs of this fact. It's been known since the greek.
pi is irrational. This is much more complicated and is a result from 19th century.
As you see, there is absolutely no mention of the digits in the definition or in the proofs I presented.
Now the result that you probably hear about and wanted to remember (slightly incorrectly) is that a number is rational if and only if its decimal expansion is eventually periodic. What does it mean ?
Take, 5/700 and write it in decimal expansion. It is 0.0057142857142857.. As you can see the pattern "571428" is repeating in the the digits. That's what it means to have an eventually periodic decimal expansion. The length of the pattern can be anything, but as long as there is a repeating pattern, the number is rational and vice versa.
As a consequence, sqrt(2) does not have a periodic decimal expansion. So it has an infinite number of digits but moreover, the digits do not form any easy repeating pattern.
An integer is a natural number (1, 2, 3 ...), zero, or the negative of a natural number.
-76.15 is none of those,
Answer: NO
Answer: 2000
Step-by-step explanation:
Answer:
Step-by-step explanation:
The graph shows the solution (-6,2)
i.e at x= -6 y=2
Analysis of each of the answers, since we can't write the equation of a straight line with only that information i.e the single point
Then,
Option 1
1. 2x - 3y = -6
x= -6 y=2
Then let insert x=-6 and y =2
2(-6)-3(2)
-12-6
-18.
Since -18 ≠ -6, then this is not the equation of the line and doesn't make up the system
Option 2
2. 4x - y = 26
Inserting x=-6 and y=2
4(-6)-(2)
-24-2
-26
Since -26 ≠ 26, then this is not the equation of the line and doesn't make up the system
Option 3
3. 3x + 2y = -14
Inserting x=-6 and y=2
3(-6)+2(2)
-18+4
-14
Since -14 ≠ -14 then this is the equation of the line and it make up the system.
Option 4
x-y = -2
Inserting x=-6 and y=2
(-6)-(2)
-6-2
-8
Since -8≠ -2, then this is not the equation of the line and doesn't make up the system
Option 5
5. x+y=-4
Inserting x=-6 and y=2
(-6)+(2)
-6+2
-4
Since -4 ≠ -4, then this is the equation of the line and it makes up the system.
Then, there are two option that make up the system
3. 3x + 2y = -14
And
5. x+y=-4
Answer:
B
Step-by-step explanation:
A proportional relationship is represented by linear function with its linear parameter "b" equal to zero. Since b is equal to zero, the line passes through the origin and the function/relation is proportional.
To verify that we divide the y coordinate over the x coordinate we obtain a constant called k, which is the slope.
For instance:
According to this function we can easily check a proportional relationship among its points:
