y-27=45

y=45+27

y=72

63 - (25+z) = 26

25+z=63-26

25+z=37

z=37-25

z=12

37+x=64

x=64-37

x=27

(x-653) + 308=417

x-653=417-308

x-653=109

x=109+653

x=762