Question

найдите корень квадратного уравнения дискриминанта
1) 9х² + 6x – 8 = 0;
1) х² – 5х + 4 = 0;
1) 2x² + 3х – 5 = 0;
2) 25x² — 10x – 3 = 0
2) х² - 3x — 10 = 0.
2) 5х² – 7x — 6 = 0​

Answer 1

1) D= 36+288= 324

x1= (-6+18)/18= 12/18= 2/3

x2= (-6-18)/18= -4/3

2) D= 25-16= 9

x1= (5+3)/2= 4

x2= (5-3)/2= 1

3) D= 9+40= 49

x1= (-3+7)/4= 1

x2= (-3-7)/4= -2,5

4) D= 100+300= 400

x1= (10+20)/50= 3/5

x2= (10-20)/50= -1/5

5) D= 9+40= 49

x1= (3+7)/2= 5

x2= (3-7)/2= -2

6) D= 49+120= 169

x1= (7+13)/10= 2

x2= (7-13)/10= -0,6