Question

Resolva as seguintes equações
d) 4 x2 - 5x + 8 = 0
e) 2x2 - 8x + 8 = 0

Answer 1

d) 4x 2 - 5x + 8 = 0.

8x - 5x = 0 - 8.

3x = -8.

x = -8/3.

e) 2x 2 - 8x + 8 = 0.

4x - 8x = 0 - 8.

-4x = -8.

4x = 8.

x = 8/4.

x = 2.

Answer 2

Resposta:

D 8/13

E) x=2

Explicação passo-a-passo:

D) 4x2-5x+8=0

4x2-5x+8=0

-4x×2-5x+8=0

-4x×2

-(4x2)x

-8x

-4x×2-5x+8=0

-8x-5x+8=0

-8x-5x

(-8-5)x

-13x

-8x-5x+8=0

-13x+8=0

-13x+8-8=0-8

-13x=0-8

-13x+8-8=0-8

-13x=-8

-13x÷(-13)=-8÷(-13)

x=-8÷(-13)

-13x÷(-13)=-8÷(-13)

x=8÷13

-13x÷(-13)=-8÷(-13)

x=8/13

13x=-8

x=8/13

Resposta

x=8/13

E) 2x2-8x+8=0

2x2-8x+8=0

2x×2-8x+8=0

2x×2

4x

2x×2-8x+8=0

4x-8x+8=0

4x-8x

(4-8)x

-4x

4x-8x+8=0

-4x+8=0

-4x+8-8=0-8

-4x=0-8

-4x+8-8=0-8

-4x=0-8

-4x+8-8=0-8

-4x=-8

-4x+8=0

-4x=-8

-4x÷(-4)=-8÷(-4)

x=-8÷(-4)

-4x÷(-4)=8÷(-4)

x=8÷4

-4x÷(-4)=-8÷(-4)

x=2

-4x=-8

x=2

Resposta

x=2