Question

2(n+5)(n-2) Cat este rezolvarea

Answer 1

[tex]2 n^{2} - 4n + 10 n - 20 = 0 [/tex]
$2 n^{2} + 6n - 20 =0$ / : 2
$n^{2} + 3n - 10 =0$

Δ= $b^{2} - 4ac$
Δ= 9+40
Δ= 49

n₁,₂= $\frac{-b +- \sqrt{Δ} }{2a}$
n₁,₂= $\frac{-1 +- \sqrt{49} }{2}$
n₁,₂= $\frac{-1 +- 7}{2}$ =>
=> n₁= $\frac{6}{2}$ = 3
=> n₂=$\frac{-8}{2}$ = -4

S={-4, 3}