Question

Fie functiile f:R->R, f(x)=x+3 si g:R->R, g(x)=2x-1.Sa se determine solutia reala a ecuatiei 2f(x)+3g(x)=-5.

Answer 1

$2f(x)+3g(x)=-5 \\ \\ 2(x+3)+3(2x-1)=-5 \\ \\ 2x+6+6x-3=-5 \\ \\ 8x=-5-6+3 \\ \\ 8x=-8 \\ \\ \boxed{x=-1}$

Answer 2

2 · ( x +3)  + 3 · ( 2x -1 )  = - 5 
2x + 6 + 6x - 3 = - 5 
8x = - 5  - 3 
8x = - 8 
x = - 1