Answer:

Step-by-step explanation:
We need to find 1/4 of the area of a circle with a radius of 8
Let r be radius
Area of a circle = 
Substitute r with 8
Area of a circle = 
Now, to find 1/4 of the area, we can create an equation 
The answer is 
Hope this helps :)
Have a spectacular day!
Answer:
14, 28, 42, 56, and 70 are the first 5 common multiples of 14
20, 40, 60, 80, and 100 are the first 4 common multiples of 20
All exercises involve the same concept, so I'll show you how to do the first, then you can apply the exact same logic to all the others.
The first thing you need to know is that, when a certain quantity multiplies a parenthesis, you can distribute that number to every element in the parenthesis. This means that

So,
is multiplying the parenthesis involving
and
, and we distributed it:
multiplies both
and
in the final result.
Secondly, you have to know how to recognize like terms, because they are the only terms you can sum. Two terms can be summed if they have the same literal expression. So, for example, you cannot sum
, and neither
exponents count.
But you can su, for example,

or

So, take for example exercise 9:

We distribute the 1.2 through the first parenthesis:

And you can distribute the negative sign through the second parenthesis (it counts as a -1 to distribute):

So, the expression becomes

Now sum like terms:

Because α varies directley to β

(k = constant)
α=7 when β=2
7= 2k
k=
so when α=21
21=

b
b= 6
Answer:
45
Step-by-step explanation:
OK, first we turn the variables into into the actual values:
The equation will look like this:
(2)5 + (-5)(-7)
Now its easier to solve! Lets solve (2)5!
2 * 5 = 10
The equation looks like:
10 + (-5)(-7)
We will also solve (-5)(-7). Remember that a negative number times a negative number is positive!
-5 * -7 = 35
Lets finish the rest:
10 + 35 = 45.
Hope this is correct and have a nice day!