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:
Golfkrieg ist die ganze Woche im Auto oder ist das 56357
Answer:
Just practice ,know different ways of solving it ,gain experince ,be smart and skilled.
Step-by-step explanation:
if you want to prove anuthing then go with the concept accoeding to the nature of the problem and there are almost many ways to prove anything so don't waste your time on way get on to the other ways.
It may not get proved at first time so keep on doing questions and when you have gained experience you know every nature of problems and then you are skilled properly.
Https://www.calculatorsoup.com/calculators/geometry-solids/surfacearea.php
use this calculator it’s super helpful with lots of these kinds of questions!
Decided by 12 is 2 your welcome
