Question

Calcule o valor do X:

Answer 1

Pelo Teorema de Tales:

$\dfrac{12}{2x-6}=\dfrac{8}{x+1}$

$8(2x-6)=12(x+1)$

$2(2x-6)=3(x+1)$

$4x-12=3x+3$

$4x-3x=12+3$

$x=15$.

Answer 2

  8    =   12  
x + 1    2x - 6

multiplica em cruz

12 (x+1) = 8 (2x - 6)
12x + 12 = 16x - 48
12x - 16x = - 48 - 12
- 4x = - 60 (-1)
4x = 60
x = 60/4
x = 15