Answer:
SSS postulate because three sides of a triangle are are congruent
Ok so factoring quadratics is fairly easy once you get the hang of it
So we have a quadratic 
My first question would be what 2 numbers multiply to -2 and add to +1
the answer is 2 and -1
Second question what 2 values multiply to get 
the answer x and x
your factored form would be 
This is as far as i can explain there is a whole lot about quadratics to be learned. You have to ask your teacher on more information
Remark
To find any common denominator, write down all the prime factors and pick out what you need to make an LCD.
Method
x has one x
2x^2 = 2 * x * x
Your LCM is
one 2
two xs.
LCM = 2*x*x
LCM = 2x^2
Answer:
6
Step-by-step explanation:
18 - 6 = 12
12/2 = 6