Question

qual a soma de (x-20) . (x+8) ?

Answer 1

x2+8x-20x-160
x2-12x-160
Δ=b2-4.a.c
Δ=(-12)2-4.2.(-160)
Δ=144-4.(-160)
Δ=144+640
Δ=784
x=-b+-√Δ
-----------
2.a
x=-(-12)+-√784
-------------------
2.1
x=12+28
--------- => x1=20
2.1
x=12-28
--------- => x2=-8
2.1