Question

RESOLVA A SEGUINTE EQUAÇÃO :

|2 4 1|
|2 4 X| = 0
|3 1 2|

A) 1
B) 0
C) _ 1
D) _ 10 ​

Answer 1

$\huge\begin{vmatrix}2&4&1\\2&4&x\\3&1&2\end{vmatrix}=0$

$\mathsf{2(8-x)-4(4-3x)+1(2-12)=0}\\\mathsf{16-2x-16+12x-10=0}\\\mathsf{10x=10}\\\mathsf{x=\dfrac{10}{10}}$

$\boxed{\boxed{\boxed{\mathsf{x=1}}}}$

$\huge\boxed{\boxed{\boxed{\mathsf{\maltese~~Alternativa~a}}}}$

Answer 2

Resposta:

A

Explicação passo-a-passo:

Calculo do determinante da Matriz = 0

16 + 12x + 2 - 12 - 2x - 16 = 0

10x - 10 = 0

10x = 10

x = 1