Question

1. Determine o valor
de x sabendo que:
DE // BC.
D
3
A
C
X + 1 E 4​

Answer 1

Resposta:

$\frac{x + 3}{x + 5} = \frac{3}{x + 1}$

$(x + 3)(x + 1) = 3(x + 5)$

${x}^{2} + 4x + 3 = 3x + 15$

${x}^{2} + x - 12 = 0$

$delta = 1 + 48 = 49$

$x = \frac{ - 1 + - 7}{2}$

$x = 3 \: ou \: x = - 4(n \: serve)$

X = 3