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(4m *0,2m)*2m=1,6m ^{2}*0,3m=0,48m ^{3} 3m-0,2m-0,2m=2,6m-II bok (2,6m*0,2m)*2m=1,04m ^(2)*0,3m= 0,3m^(3) Odp: Zużyto 0,8m sześciennego.

a) [(6a+7)/7] - 3 = (5a - 3)/8 /*56 (56/7)*(6a+7) - 3*56 = (56/8)*(5a - 3) 8*(6a+7) -168 = 7*(5a - 3) 48a + 56 - 168 = 35a - 21 13a = 91 /: 13 a = 7 b) (b - 4)/5 = 9 - [(2b - 41)/9] /*45 (45/5)*(b - 4) = 9*45 - (45/9)*(2b - 41) 9*(b - 4) = 405 - 5*(2b - 41) 9b - 36 = 405 - 10b + 205 19b = 646 /:19 b = 34 c) 10 - [(3c - 1)/2] = (6c + 3)/11 /*22 22*10 - (22/2)*(3c - 1) = (22/11)*(6c + 3) 220 - 11*(3c - 1) = 2*(6c + 3) 220 - 33c + 11 = 12c + 6 225 = 45c /:45 c = 5 d) 2 - [(3a - 7)/4] + [(a + 17)/5] = 0 /*20 20*2 - (20/4)*(3a - 7) + (20/5)*(a + 17) = 0 40 - 5*(3a - 7) + 4*(a + 17) = 0 40 - 15a + 35 + 4a + 68 = 0 -11a = -143 /:(-11) a = 13 e) [(b+6)/2] + [(5 - 4b)/3] = (8 - b)/6 /*6 (6/2)*(b+6) + (6/3)*(5 - 4b) = (6/6)*(8 - b) 3*(b+6) + 2*(5 - 4b) = 8 - b 3b + 18 + 10 - 8b = 8 - b -4b = -20 /:(-4) b = 5 f) [(9c + 7 - 2c)/2] + (c - 2)/7 = 36 [(7c + 7)/2] + (c - 2)/7 = 36 /*14 (14/2)*(7c + 7) + (14/7)*(c - 2) = 504 7*(7c + 7) + 2*(c - 2) = 504 49c + 49 + 2c - 4 = 504 51c = 459 /:51 c = 9