1)

[tex]2 {x}^{2} + 7x + 6 = 0 \\ d = {7}^{2} - 4 \times 2 \times 6 = 49 - 48 = 1 \\ x_{1} = \frac{ - 7 + 1}{2 \times 2} = - \frac{6}{4} = - 1.5\\ x _{2} = \frac{ - 7 - 1}{2 \times 2} = - \frac{8}{4} = - 2[/tex]

2)

[tex] {x}^{2} - 10x + 25 = 0 \\ ( {x} - 5) {}^{2} = 0 \\ x - 5 = 0 \\ x = 5[/tex]