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:
Answer:
[See Below]
Step-by-step explanation:
❶ It is irrational because to make it repeating it must be <u>EXACT</u>. In this case it is adding a 0 after every 1. So it'd be irrational since it doesn't have an end.
❷ Irrational because no one knows the end of pi. It doesn't have an ending so therefore irrational.
~<em>Hope this helps Mate. If you need anything feel free to message me. </em>
➻ In a group of 40 people, 27 can speak English and 25 can speak Spanish.
➻ The required number of people who can speak both English and Spanish .
<u>Consider</u> ,
➻ A → Set of people who speak English.
➻ B → Set of people who speak Spanish
➻ A∩B → Set of people who can speak both English and Spanish
➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - n (A∩B)
➻ 40 = 52 - n (A∩B)
➻ n (A∩B) = 52 - 40
➻ ∴ n (A∩B) = 12
∴ Required Number of persons who can speak both English and Spanish are <u>12 .</u>
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➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - 12
➻ 40 = 52 - 12
➻ 40 = 40
➻ ∴ L.H.S = R.H.S
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The answer is 46. .1 times 200 is 20. then .23 times 200 is 46
For the smaller triangle ;
15^2 + b^2 = 17^2
b = 8
To check the work
15^2 + 8^2 = 289
17^2 = 289
(This is if the bottom number on the smaller triangle says 15, its a bit hard to read..)
