Question

решить уровнение х^+3х=4

Answer 1

х^2+3х=4

х^+3х-4 =0
D = 3^2 - 4*1*(-4) = 9 + 16 = 25 = 5^2

x1 = -3+5 / 2 = 2/2 = 1
x2 = -3-5 / 2 = -8/2 = -4

Answer 2

D = b^2 - 4ac