Răspunsuri

2014-05-07T20:50:10+03:00
A)x²+4x=x(x+4)
x(x+4)=0⇒x+4=0⇔x=-4
b)x²-x=x(x-1)
X(X-1)=0⇔X-1=0⇔X=1
c)2x²-x=x(2x-1)
x(2x-1)=0⇔2x-1=0⇔2x=1⇔x=1/2
d)5x²+3x=x(5x+3)
x(5x+3)=0⇔5x+3=0⇔5x=-3⇔x=-3/5
e)x²-9=0⇔x²=9⇒x=3 sau x=-3
f)x²=16⇒x=4 sau x=-4