a fost răspuns

x sa aprtina lui R ; (3x+4)totul la 2 = (2x+1)totul la 2

Răspuns :

Miky93ask
9xpatrat+24x+16=4xpatrat+4x+1 9xpatrat+24x+16-4xpatrat-4x-1=0 5xpatrat+20x+15=0 5(xpatrat+4x+3)=0 xpatrat+x+3x+3=0 x(x+1)+3(x+1)=0 (x+1)(x+3)=0 x+1=0 x+3=0 x=-1 x=-3
9x²+24x+16=4x²+4x+1
9x²-4x²+24x-4x+16-1=0
5x²+20x+15=0 
5(x²+4x+3)=0
x²+4x+3=0
Δ=b²-4ac
Δ=16-4·3=16-12=4
xunu=(-b+√Δ)/2a
xunu=(-4+2)/2=-2/2=-1
xdoi=(-4-2)/2=-6/2=-3
S={-1, -3}

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