public function testSolveEquationForZero(array $A, array $b, array $x, array $zeros)
{
$A = MatrixFactory::create($A);
$x = new Vector($x);
$b = (new Vector($b))->asColumnMatrix();
$z = (new Vector($zeros))->asColumnMatrix();
// Ax - b
$R = $A->multiply($x)->subtract($b);
$this->assertEquals($z, $R, '', 0.01);
}