Hard Matchstick Puzzles

#444: Fix 3-8=9 hard #445: Fix 9-0=8 hard #448: Fix 6-8=12 hard #449: Fix 0+5=73 hard #451: Fix 8-2=18 hard #454: Fix 8+2=5 hard #457: Fix 0-8=0 hard #459: Fix 2-9=17 hard #462: Fix 6-4=70 hard #475: Fix 1-9=70 hard #476: Fix 4+0=72 hard #477: Fix 3-9=72 hard #479: Fix 7-9=76 hard #484: Fix 4+9=72 hard #490: Fix 8-2=11 hard #501: Fix 8-2=2 hard #503: Fix 8-3=9 hard #504: Fix 7+0=75 hard #506: Fix 4-8=4 hard #508: Fix 9+1=2 hard #509: Fix 9-8=18 hard #512: Fix 8-8=76 hard #513: Fix 7-9=18 hard #514: Fix 5-9=74 hard #519: Fix 5-6=17 hard #520: Fix 6-9=14 hard #522: Fix 8-6=15 hard #526: Fix 1+9=76 hard #529: Fix 6-8=15 hard #536: Fix 1+3=70 hard #540: Fix 3+0=71 hard #542: Fix 6+0=8 hard #548: Fix 1-5=8 hard #552: Fix 4-6=9 hard #555: Fix 5+8=74 hard #556: Fix 6-9=75 hard #558: Fix 7-8=75 hard #560: Fix 8+6=76 hard #569: Fix 8-2=8 hard #570: Fix 5-1=8 hard #572: Fix 7-4=71 hard #573: Fix 9+8=0 hard #575: Fix 7-8=9 hard #576: Fix 8-0=6 hard #578: Fix 8+9=76 hard #584: Fix 1-9=18 hard #585: Fix 8-9=18 hard #587: Fix 8-4=72 hard