Question

Rezolvat prin ecuatia de gradul al doilea :
b) 2x²+7x-4=0

Answer 1

2x²+7x-4=0
Δ=b²-4ac
Δ=7²-4·2·(-4)=49+32=81
x1=(-7+9)/4=2/4=1/2
x2=(-7-9)/4=-16/4=-4
S={-4,1/2}

Answer 2

$delta = b^{2} -4ac = 49 +4*2*4=49+32=81 \\ x_{1}= \frac{-7-9}{4}= \frac{-16}{4}=-4 \\ x_{2}= \frac{-7+9}{4}= \frac{2}{4}= \frac{1}{2}$
S={-4, 1/2}