Question

A) x elevado a 2 3=4x
B) -20=-x-x elevado a 2

Answer 1

letra b
x^2+x+20=0
Δ= 1^2-4×1×20
Δ=1+80
Δ=81
x= -1+9
     2-1
x'=8
x"=-1-9
      2-1
x"=-10