Решите плиз 2x^2-9x-5=0

Question

Решите плиз 2x^2-9x-5=0

Answer 1

D=b² -4ac= ( - 9 )² -  4*2* ( - 5 ) =81+40=121
√D=11
x1= - b+√D / 2a = 9+11 / 4 = 5
x2 = - b - √D / 2a = 9 - 11 / 4 = - 2 / 4 = - 1 / 2 = - 0 ,5
Ответ: 5 ; - 0,5.

Answer 2

2x²-9x-5=0
D = b²-4ac
D = (-9)² - 4 · 2 · (-5) = 81+40 = 121
√D=√121=11
x1=-b+√D\2a
x1 = 9+11\4 = 20\4 = 5
x2=-b-√D\2a
x2 = 9-11\4 = -2\4 = -1\2 = -0,5
Ответ: x1 = 5; x2 =-0,5