Question

Calculati: (2x-3)(2x+3)= 13x+4-7x-8= Descompuneti in factori: 4x+8=

Answer 1

1).  ...  4x²-9=6x-4  ⇔  4x²-6x-5=0  ⇒ Δ=36-4*4*(-5)=36+80=116  adica:  √Δ=2√29
      $x_{1;2}=\frac{6\pm2\sqrt29}{8}\rightarrow\;x_{1;2}=\frac{3\pm\sqrt{29}}{4}$;
2).  ...  4x+8 = 4(x+2) ;

Answer 2

4x+8=4(x+2)
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