Found one error in Example-27

$factValue = $number * (Get-Factorial($number – 1))

should be

$factValue = $number * (Factorial-Of-A-Number($number – 1))

Take exactly 2 arguments: $Point1and $Point2
each is a pair of (x,y)coordinates
Return a string of the format “y = mx + b”, where m and b are solved for
Format m and b so they are nice to read (1.23 instead of 1.23456789)
Return “Points are identical” if the inputs are the same
Return “Undefined Slope” if line is a straight vertical line
Make sure inputs to the function are valid, thus only one error is printed

Any ideas? I tried but it is not working

good works