Question

Determinati numarul real m pentru care:
a)ecuatia 2x-m(x+3)=7mx+12are solutia 5
b)ecuatia -3x+4(mx-1)=6x+2-7(m+2)are solutia 3
c)ecuatia 3(m-1)(x+2)-2(2m-1)(2x+1)=7x+3mx-5are solutia -3

Answer 1

a) 10-m(5+3)=35m+12
10-8m=35m+12
10-12=35m+8m
-2=43m
m=-2/43
b)-9+4(3m-1)=18+2-7(m+2)
-9+12m-4=18+2-7m-14
19m=13+20-14
19m=19
m=1
c) (3m-3)(-1)-2(2m-1)(-5)=-21-9m-5
-3m+3+20m-10=-26-9m
17m+9m=7-26
26m=-21
m=-21/26