Question

Daca ax-2bx+cx=32,a-b=-9 si c-b=-7,aflati x

Answer 1

ax-2bx+cx=ax-bx-bx+cx=x(a-b)+x(c-b)=x·(-9)+x·(-7)=32⇒
-9x-7x=32
-16x=32
x=-32:16=-2

Answer 2

ax-2bx+cx=32
o sa facem un artificiu, si -2bx o sa il descompunem in -bx-bx. 

ax-bx-bx+cx=32
x(a-b)+x(c-b)=32
-9x+(-7)x=32
-9x-7x=32
-16x=32
x=-2