The answer is -i. I hope that helps.
30^2=900
55^2=3025
900+3025=3925
Square root of 3925==64.6298
This is Pythagoras Theorem where A^2+B^2=C^2 square root of C is answer hope this helped, the answer is 64.63
V is at (-1,-1)
by reflecting it across the y axis its x coordinate gets inverted:
V'=(-1*-1,-1)=(1,-1)
so the second option is the correct one
Ooh ooh i think i know its y = 3x