20 Rezolvați următoarele ecuații: a 5(2x-1)+3(x-1)-6(7x-12)=15(8 – X)-84 ; b 2(3x +4) - 3x-2=6(2x - 3)+2(3-4x) +5(2x-3); 49x - 4)+2(2x - 7)-7x=3(3x - 10)+5(x-22)-4; d 2(5x - 4)-(3x + 2) +11=-3(-5x+10) + 3x-6(4x-3).
Răspunsuri la întrebare
Explicație pas cu pas:
a) 5(2x-1)+3(x-1)-6(7x-12)=15(8 – X)-84
10x-5+3x-3-42x+72=120-15x-84
10x+3x-42x+15x=120-84+5+3-72
13x-42x+15x=36+5+3-72
-29x+15x=41+3-72
-14x=44-72
-14x=-28
x=-28:(-14)=>x=2
b) 2(3x +4) - 3x-2=6(2x - 3)+2(3-4x) +5(2x-3)
6x+8-3x-2=12x-18+6-8x+10x-15
6x-3x-12x+8x-10x=-18+6-15-8+2
3x-12x+8×-10x=-12-15-8+2
-9x+8x-10x=-27-8+2
-x-10x=-35+2
-11x=-33
x=-33:(-11)=>x=3
c) 4(9x - 4)+2(2x - 7)-7x=3(3x - 10)+5(x-22)-4
36×-16+4x-14-7x=9x-30+5x-110-4
36x+4x-7x-9x-5×=-30-110-4+16+14
40x-7x-9x-5x=-140-4+16+14
33x-9x-5x=-144+16+14
24x-5x=-128+14
19x=-114
x=-114:19=>x=-6
d) 2(5x - 4)-(3x + 2) +11=-3(-5x+10) + 3x-6(4x-3)
10x-8-3x+2+11=15x-30+3x-24x+18
10x-3x-15x-3x+24x=-30+18+8-2-11
7x-15x-3x+24x=-12+8-2-11
-8x-3x+24x=-4-2-11
-11x+24x=-6-11
13x=-17
La D nu stiu de ce nu imi da, dar e 04:32 dimineata si n-am dormit deloc, vezi tu ce am gresit