Answer:
Part 1) 
Par 2) 
Part 3) 
Step-by-step explanation:
step 1
Find the 
we have

Remember that

therefore

step 2
Find the 
we know that

we have

substitute




square root both sides

we have that
---> given problem
so

step 3
Find the 
we know that

we have


substitute

Simplify

Answer:
45%
Step-by-step explanation:
There are 5 A's out of a total of 11 letters which is 5/11. 5/11 as a decimal is 0.45 which, as a percentage, is 45%
You haven't provided the required roots, but I can tell you how to do this kind of exercises in general.
If the
coefficient is 1, i.e. the equation is written like
, then you can say the following about the coefficients b and c:
is the opposite of the sum of the roots
is the multiplication of the roots.
So, for example, if we want an equation whose roots are 4 and -2, we have:
So, the equation is 
If your roots are rational, you can work like this: suppose you want an equation with roots 3/4 and 1/2. You have:
And so the equation is

In order to have integer coefficients, you can multiply both sides of the equation by 8:
