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
I think its A because a and b are not the same answer and a is the correct one i think
(x-5)(x-5)
x*x-5*x-5*x-5*-5
x^2-5x-5x+25
x^2-10x+25
Answer: x=12
Step-by-step explanation:
1/3 x -4
1/3x=4 <---- First add 4 to each side of the equation (moves the "-4")
1/3x(3)=4(3) <---- Muliply each side by "3" to get rid of the fraction
x=12