Question

Dau coroana urgent va rog!


Sa se rezolve in multimea numerelor naturale ecuatiile;



2x+5=7

3x-21=45

20-7x=243

5*(x-9)=135

12*(x-5)=144

15*(18-x)=180

63:(x-2)=7

9*(2x+1)=153

14x+28x=588

Answer 1

2x+5=7;

2x=7-5;

2x=2;

x=2:2;

x=1;

3x-21=45;

3x=45+21;

3x=66;

x=66:3;

x=22;

20-7x=243;

20-243=7x;

-223=7x;

x=mulțimea vidă;

5*(x-9)=135;

5x-45=135;

5x=135+45;

5x=180;

x=36;

12*(x-5)=144;

x-5=144:12;

x-5=12;

x=12+5;

x=17;

15*(18-x)=180;

18-x=180:15;

18-x=12;

x=18-12;

x=6;

63:(x-2)=7;

x-2=63:7;

x-2=9;

x=9+2;

x=11;

9*(2x+1)=153;

2x+1=153:9;

2x+1=17;

2x=16;

x=8;

14x+28x=588;

42x=588;

x=588:42;

x=14;