Medium Arithmetic Puzzles

#2798: 6 _ 3 _ 9 _ 7 = -5 medium #2800: 6 _ 3 _ 9 _ 8 = -6 medium #2805: 6 _ 4 _ 2 _ 3 = 12 medium #2806: 6 _ 4 _ 2 _ 4 = 14 medium #2807: 6 _ 4 _ 2 _ 5 = 16 medium #2812: 6 _ 4 _ 2 _ 7 = -8 medium #2819: 6 _ 4 _ 2 _ 5 = 15 medium #2822: 6 _ 4 _ 2 _ 8 = 11 medium #2823: 6 _ 4 _ 2 _ 8 = -5 medium #2825: 6 _ 4 _ 2 _ 9 = -6 medium #2826: 6 _ 4 _ 3 _ 2 = 12 medium #2830: 6 _ 4 _ 3 _ 9 = -6 medium #2845: 6 _ 4 _ 4 _ 2 = 14 medium #2846: 6 _ 4 _ 4 _ 8 = 8 medium #2850: 6 _ 4 _ 5 _ 2 = 16 medium #2852: 6 _ 4 _ 5 _ 2 = 15 medium #2853: 6 _ 4 _ 6 _ 3 = 14 medium #2854: 6 _ 4 _ 6 _ 8 = 9 medium #2861: 6 _ 4 _ 6 _ 4 = 16 medium #2866: 6 _ 4 _ 6 _ 4 = 13 medium #2868: 6 _ 4 _ 6 _ 5 = 14 medium #2870: 6 _ 4 _ 6 _ 6 = 15 medium #2879: 6 _ 4 _ 7 _ 2 = -8 medium #2888: 6 _ 4 _ 8 _ 5 = 8 medium #2891: 6 _ 4 _ 8 _ 7 = 10 medium #2892: 6 _ 4 _ 8 _ 7 = -4 medium #2893: 6 _ 4 _ 8 _ 8 = -5 medium #2895: 6 _ 4 _ 8 _ 9 = -6 medium #2897: 6 _ 4 _ 8 _ 2 = 10 medium #2909: 6 _ 4 _ 9 _ 3 = -6 medium #2912: 6 _ 5 _ 2 _ 4 = 16 medium #2914: 6 _ 5 _ 2 _ 6 = -9 medium #2916: 6 _ 5 _ 2 _ 4 = 15 medium #2918: 6 _ 5 _ 2 _ 2 = 13 medium #2923: 6 _ 5 _ 2 _ 9 = 6 medium #2926: 6 _ 5 _ 3 _ 9 = 10 medium #2930: 6 _ 5 _ 3 _ 3 = 13 medium #2931: 6 _ 5 _ 3 _ 4 = 14 medium #2941: 6 _ 5 _ 4 _ 2 = 16 medium #2944: 6 _ 5 _ 4 _ 8 = -4 medium #2945: 6 _ 5 _ 4 _ 2 = 15 medium #2946: 6 _ 5 _ 6 _ 3 = 16 medium #2947: 6 _ 5 _ 6 _ 2 = -9 medium #2951: 6 _ 5 _ 6 _ 3 = 15 medium #2954: 6 _ 5 _ 8 _ 4 = -4 medium #2956: 6 _ 5 _ 9 _ 3 = 10 medium #2963: 6 _ 6 _ 2 _ 6 = 13 medium #2967: 6 _ 6 _ 3 _ 2 = 15 medium