Question

Resolva as equações abaixo, equação de segundo grau
a) 4x²+12x+5=0

b) x²+20x+19=0

c) 2x²+100x+64=0

d) X² +18x+72=0

Answer 1

Resposta:

A)

4x²+12x+5=0

4x²+10x+2x+5=0

2x×(2x+5)+2x+5=0

(2x+5)×(2x+1)=0

2x+5=0

2x+1=0

x=-5/2

x=-1/2

x₁=-5/2, x₂=-1/2

B)

x²+20x+19=0

x²+19x+x+19=0

x×(x+19)+x+19=0

(x+19)×(x+1)=0

x+19=0

x+1=0

x=-19

x=-1

x₁=-19, x₂=-1

C)

2x²+100x+64=0

x²+50x+32=0

x=-50+√50²-4×1×32/2×1

x=-50+√2500-128/2

x=-50+√2372/2

x=-50+2√593/2

x=-50+2√593/2

x=-50-2√593/2

x₁=-25-√593, x₂=-25+√593

D)

x² +18x+72=0

x² +12x+6x+72=0

x×(x+12)+6(x+12)=0

(x+12)×(x+6)=0

x+12=0

x+6=0

x=-12

x=-6

x₁=-12, x₂=-6

ESPERO QUE TENHA AJUDADO!

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