Question

X² + x -72 =0 Qual e a resposta ? por favor

Answer 1

x² +x -72 = 0
Δ= (1)² -4.1.-72
Δ= 1 + 288
Δ= 289
x= -b +-√289/2.a
x= -1 +- 17/2

x¹ = -1 + 17/2 = 16/2 = 8

x² = -1 -17/2 = -18/2 = -9                     S= {8;-9}

Answer 2

X² + x -72 = 0
a = 1; b = 1; c = - 72
∆ = b^2 - 4ac
∆ = 1^2 - 4.1.(-72)
∆ = 1 + 288
∆ = 289

x = [ - b +/- √∆]/2a
x = [ - 1 +/- √289]/2.1

x' = [ - 1 +17]/2 = 16/2 = 8
x" = [ - 1 -17]/2 = - 18/2 = - 9

Resp.: { 8; - 9}