Adding the value with setters and getters to an array PHP

Hi guys I was just wondering how would I use setters and getters to add values (int) into my two arrays from which I have to calculate the euclidean distance later on in the code. This is what I have so far, I have tried several times and for several hours but the way I tried obviously doesn't work.

abstract class Euclidean
{
    protected $pointA=array();
    protected $pointB=array();

    public function Calculate($pointA, $pointB)
    {
        $n = count($pointA);
        $sum = 0;
        for ($i = 0; $i < $n; $i++) {
           $sum += ($pointA[$i] - $pointB[$i]) * ($pointA[$i] - $pointB[$i]);
           echo sqrt($sum);
        }
        return sqrt($sum);
    }

    public function setpointA($x)
    {
        $this->pointA = $x;
    }

    public function getpointA()
    {
        return $this->pointA;
    }

    public function setpointB($y)
    {
        $this->pointB = $y;
    }

    public function getpointB()
    {
        return $this->pointB;
    }
}

UPDATE

public function setpointA($pointA)
{
    parent::setpointA($pointA=1&&3&&9&&2);
}


public function getPointA()
{
    return $this->pointA;
}

public function setpointB($pointB)
{
    parent::setpointB($pointB=7&&2&&3&&9);
}

public function getpointB()
{
    return parent::getpointB();
}