Could someone please help me justify each line of my proof with this theorem

Use This Theorem To justify each part of your proof: Theorem: Let x,yiz be real numbers. ( a ) If x + 2 =y+ 2 , Then x=y. ( 6 ) x . 0 = 0 (c ) ( - 1 ) . x = - x (d ) xy =0 iff x= 0 or y= 0. (e)xay iff - yc-x ( f ) If x 1 x / = 1 x - y + y / = [ x- y/ + ly| by the Triangle inequality = 7 1 x 1 - 14/ = 1 x - 4 1 7 Since | x - y/ > | x /