Question

-5x la a doua + 2x +3=0

Answer 1

-5x^2 + 2x + 3 = 0   => a=-5   => b=2  => c=3

delta = b^2 - 4ac
delta =(2)^2 - 4*(-5)*3
delta = 4+60
delta = 64 => √64=8

x1,2 = -b + sau - √delta /2a 

x1= (-2 - 8)/2*(-5) = -10/-10= +1 

x2= (-2+8)/2*(-5) = 6/-10 = 3/-5

x∈(1; 3/-5)