Question

rezolvati ecuatiile :

-9+7x=5x+11
6x-13=2x-1
2x-3(1,5x+2=4,7
5x-9+2x=19
2x+$\frac{1}{2}$=-0,75+$\frac{1}{3} }$ x

Answer 1

-9+7x=5x+11 => 7x-5x=11+9 => 2x=20 => x=10
6x-13=2x-1 => 6x-2x=-1+13 => 4x=12 => x=3
5x-9+2x=19 => 5x+2x=19+9 => 7x= 28 => x=4
2x+$\frac{1}{2}$=-0,75+$\frac{1}{3} x$ =>
Rationalizam ecuatia in partea din stanga, prima ecuatie cu 2 iar in partea din dreapta, prima ecuatie cu 3, iar a doua cu 4
$\frac{2*2x+1}{2} = -\frac{3}{4} + \frac{1}{3}x$ =>
$\frac{4x+1}{2} = -\frac{9+4x}{12}$
Rationalizam cu 6 in partea din stanga a semnului egal si obtinem
$\frac{6(4x+1)}{12} = -\frac{9+4x}{12}$
Efectuam calculul din partea stanga a ecuatie si simplificam toata ecuatia cu 12 obtinand
$24x+6=-9-4x$ => $24x+4x=-9-6 =\ \textgreater \ 28x=-15 =\ \textgreater \ x=- \frac{15}{28}$
2x-3(1,5x+2)=4,7 => 20x-45x-60=47 => -25x=107 =>
x=$- \frac{107}{25}$