Given:
Expression is

To prove:
If r is any rational number, then
is rational.
Step-by-step explanation:
Property 1: Every integer is a rational number. It is Theorem 4.3.1.
Property 2: The sum of any two rational numbers is rational. It is Theorem 4.3.2.
Property 3: The product of any two rational numbers is rational. It is Exercise 15 in Section 4.3.
Let r be any rational number.
We have,

It can be written as

Now,
3, -2 and 4 are rational numbers by property 1.
is rational by Property 3.
are rational by Property 3.
is rational by property 2.
So,
is rational.
Hence proved.
Answer: 
Step-by-step explanation:
Since the center of dilation is not at the origin, we can use the following formula in order to find the coordinates of the vertices of the triangle D'E'F':

Where "O" is the center of dilation at (a,b) and "k" is the scale factor.
In this case you can identify that:

Therefore, susbtituting values into the formula shown above, you get that the coordinates ot the resulting triangle D'E'F, are the following:
Vertex D' → 
Vertex E' → 
Vertex F' → 
Answer:
area of trapezium: -
formula...
½(sum of parallel sides)×height=area
=>240=½(12+x)×12
=>240=(12+x)×6
=>240=60+6x
=>6x=240-60
=>6x=180
=>x=180/6
=>x=30cm
therefore, the value of x is 30 cm.
Step-by-step explanation:
hope it helps u
<u>Answers </u><u>with </u><u>Method</u><u>:-</u>
1) Multiply the length value by 100,000.


2) For this, divide the length value by 1000.


3) For finding the approximate value, just multiply the value of length by 1.609.


4) Multiply the given mass value by 100.


5) Multiply the given value by 10,000.

