Question

Resolva as equações x² = 4_5 x + 1_5

Answer 1

Explicação passo-a-passo:

x²=4-5x+1-5

2x=4-5x+1-5

2x+5x=4+1-5

7x=5-5

7x=0

Answer 2

Resposta:

$x^2={4\over5}x+{1\over5}x\\ \\ mmc=5\\ \\ 5x^2=4x+1\\ \\ 5x^2-4x-1=0$

a=5

b=-4

c=-1

Δ=b²-4ac

Δ=(-4)²-4(5)(-1)

Δ=16+20

Δ=36

$x={-b\pm\sqrt{\Delta} \over2a}={-(-4)\pm\sqrt{36} \over2.(5)}={4\pm6\over10}\\ \\ x_1={4-6\over10}=-{2\over10}=-{1\over5}\\ \\ x_2={4+6\over10}={10\over10}=1\\ \\ S=\{-{1\over5},1\}$