'**SUMMARY**
Checks whether two lines are perpendicular or not.
**RETURNS**
Bool. True or False
**EXAMPLE**
>>> img = Image("lenna")
>>> l = img.findLines()
>>> c = l[0].isPerpendicular(l[1])'

def isPerpendicular(self, line):

    if (self.slope == float('inf')):
        if (line.slope == 0):
            return True
        return False
    if (line.slope == float('inf')):
        if (self.slope == 0):
            return True
        return False
    if ((self.slope * line.slope) == (-1)):
        return True
    return False
