Question

Рлзвяжіть рівняння:

2x²+9x+4=0

Answer 1

2
x
2
+
9
x
+
4
=
0
2

2
+
9

+
4
=
0
(
2
x
+
1
)
(
x
+
4
)
=
0
(
2

+
1
)
(

+
4
)
=
0

1
2
x
=
−
4


=
−
1
2

=
−
4

Answer 2

$2 {x}^{2} + 9x + 4 = 0 \\ a = 2\\ b =9 \\ c = 4\\ D = {b}^{2} - 4ac = {9}^{2} - 4 \times 2 \times 4 = 81 - 32 = 49 \\ x_{1} = \frac{ - 9 - 7}{2 \times 2} = - \frac{16}{4} = - 4 \\ x_{2} = \frac{ - 9 + 7}{2 \times 2} = - \frac{2}{4} = - 0.5$