I need help please help

[6, 18]

Step-by-step explanation:

the first matrix has the dimensions 1 x 2 (1 row, 2 columns).  The send has the dimensions 2 x 2.  Because of this it is possible to do matrix multiplication and the result will be a 1 x 2 matrix.

Multiply the column -2,  7 by the row 4, 2:

We get (-2)(4) + (7)(2), which simplfies to 6.  This is the first element of the 1 x 2 product.

Multiply the column 5, -1 by the row 4, 2:  We get (5)(4) + (-1)(2), or 18.

The fourth answer choice is the correct one:  [6, 18]

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!