Question

Me ajudem pfv. 25 pontos
Escreva as seguintes equaçoes de forma reduzida
a) (3x-4).(3x+1)=14-9x
b) (x+5).(x-4)=x+16

Answer 1

a) (3x-4).(3x+1)=14-9x

9x^2 + 3x - 12x - 4 = 14 -9x
9x^2 -9x - 4 = 14 - 9x
9x^2 - 9x + 9x = 14 + 4
9x^2 = 18
x^2 = 18/9
x^2 = 2
x = √2

b) (x+5).(x-4)=x+16

x^2 -4x + 5x - 20 = x + 16
x^2 + x - 20 = x + 16
x^2 + x + x = 16 + 20
x^2 + 2x = 36
x^2 + 2x - 36 = 0

Answer 2

Oie, Td Bom?!

a)

$(3x - 4) \: . \: (3x + 1) = 14 - 9x$

$9x {}^{2} + 3x - 12x - 4 = 14 - 9x$

$9x {}^{2} - 9x - 4 = 14 - 9x$

$9x {}^{2} - 4 = 14$

$9x {}^{2} - 4 - 14 = 0$

$9x {}^{2} - 18 = 0$

b)

$(x + 5) \: . \: (x - 4) = x + 16$

$x {}^{2} - 4x + 5x - 20 = x + 16$

$x {}^{2} + x - 20 = x + 16$

$x {}^{2} - 20 = 16$

$x {}^{2} - 20 - 16 = 0$

$x {}^{2} - 36 = 0$

Att. Makaveli1996