aratati ca a=3 este solutie a ecuatiei:

Explicație pas cu pas:
7(4x-12)/35+5(17-6x)/35=x/2+7(-2x-1)/35-10/35
28x-84/35+85-30x/35=x/2+(-14x)-7/35-10/35
55x-168/70+170-60x/70=35x/70-28-14/70-20/70 /×70
55x-168+170-60x=35x+28x+14-20
-5x+2=63x-6
-5x-63x=-6-2
-24x=-8
x=3