Question

(x+1)(x+2)=56
clasa a V a
Urgentttt

Answer 1

Cautam doua numere consecutive care inmultite dau 56
Singura varianta este 7 si 8
x+1 = 7
x+2 = 8
x = 6

Answer 2

(x+1)(x+2)=56
56=7×8
(x+1)(x+2)=7×8
x+1=7   x=6
x+2=8  x= 6

56=(-7)×(-8)
(x+1)(x+2)=(-8)×(-7)
x+1=- 8  x=-9
x+2=-7  x=-9

sau
ecuatie de gr.2
(x+1)(x+2)=56
x²+x+2x+2-56=0
x²+3x-54=0
Δ=9+4x54=9+216=225
x₁=(-3+√225)/2=(-3+15)/2=6
x₂=(-3-√225)/2=(-3-15)/2=-9