a)5/3=a/2 3a=5*2 3a= 10 a= 10/3 b)3/10 = x/4 10x = 3*4 10x= 12 x = 12/10 x = 6/5 c) 7/14 =m 21 14m = 7*21 14m = 147 m = 147/14 d)2/m = 3/7 3m = 14 m= 14/3 e) 3/x =7/x=5 7x = 3x+15 7x - 3x= 15 4x = 15 x = 15/4 f)m+4/2=m-3/5 2m-6=5m+20 2m-5m = 20+6 -3m=26 m = -26/3 g)a+3/5=7/5 5a+15=7*5 5a = 35 - 15 5a= 20 a = 4 h) x-2/3 =2x+7/5 6x+21=5x-10 x = -31 5/2m+5=2/4m-1 20m-5=4m+10 16m=15 m = 15/16
a)5/3=a/2 (stosujemy metodę na "krzyża") 3a= 5*2 3a=10/:3 a = 3⅓ b)3/10=x/4 10x=3*4 10x=12/:10 x = 1,2 c)7/14=m/21 14m=7*21 14m=147/:14 m=10,5 d)2/m=3/7 3m=2*7 3m=14/:3 m=4⅔ e)3/x=7/x+5 7x=3(x+5) 7x=3x+15 7x-3x=15 4x=15/:4 x=3,75 f)m+4/2=m-3/5 2(m-3)=5(m+4) 2m-6=5m+20 2m-5m=20+6 -3m=26/-3 m= -8⅔ g)a+3/5=7/5 5(a+3)=7*5 5a+15=35 5a=35-15 5a=20/:5 a=4 h)x-2/3=2x+7/5 5(x-2)=3(2x+7) 5x-10=6x+21 5x-6x=21+10 -1x=31/-1 x=-31 i)5/2m+5=2/4m-1 5(4m-1)=2(2m+5) 20m-5=4m+10 20m-4m=10+5 16m=15/:16 m=15/16
