Question

А) -2(а+5)+3=2-3(а+1) б) 0,2(м-2)-0,4(м+3)=0,4-0,6м в) 0,2(у-3)-1=0,5(у+3)-0,4 г) 0,3(n-4)-0,7(n-3)=4,9-0,9n решить !

Answer 1

А)-2a-10+3=2-3a-3 
-2a-7=-3a-1 
-2a+3a=-1+7
;a=6
-2(6+5)+3=2-3(6+1) 
-19=-19
б)0,2m-0.4-0.4m-1.2=0.4-0.6m 
-0.2m-1.6=0.4-0.6m 
 -0.2m+0.6m=0.4+1.6 
 0.4m=2
m=5
0.2(5-2)-0.4(5+3)=0.4-0.6*5
2.6=2.6
в)0,2y-0.6-1=0.5y+1.5-0.4 
0.2y-1.6=0.5y+1.1 
0.2y-0.5y=1.1+1.6 
 -0.3y=2.7 
 y=-9 
 0.2(-9-3)-1=0.5(-9+3)-0.4
-3.4=-3.4
г)0,3n-1.2-0.7n+2.1=4.9-0.9n
-0.4n+0.9=4.9-0.9n
-0.4n+0.9n=4.9-0.9
0.5n=4
n=8
0.3(8-4)-0.7(8-3)=4.9-0.9*8
-2.3=-2.3