I will do my best to explain this “ x method “ I use
Basically, two factors of the first and last number must multiply together to sum up to equal the middle number
1 X 12
1 4
(x+12) (x+4)
Hope this helps!


Therefore, (1/7)³ = 1/343, implying that the answer is option (D).
Hope it helps. :)
(3+4i)*4 = 3*4+4i*4 = 12+16i
The complex number 12+16i is in the form a+bi where a = 12 and b = 16
m = modulus
m = distance from (0,0) to (a,b)
m = sqrt(a^2+b^2)
m = sqrt(12^2+16^2)
m = sqrt(144+256)
m = sqrt(400)
m = 20
Answer: 20