Question

молю, решите, даю 15 баллов

Answer 1

x₁ * x₂ = 195 : 12
x₁ * x₂ = 16,25
x₂ = 16,25 : (- 3,75) = - 13/30

x₁ + x₂ = - 3,75 - 13/30 = - 4 11/60
$- \frac{b}{12}=-4 \frac{11}{60}\\\\b=-4 \frac{11}{60} *(-12) = 50,2$

Answer 2

12х² + bx  + 195 = 0   
х₁  =  - 3,75 
12 * ( - 3,75)²  + b* (-3,75) + 195 = 0
12  * ( - ¹⁵/₄)²    -  3.75b   + 195  = 0
¹²/₁  *  ²²⁵/₁₆    - 3.75b  + 195  = 0
⁶⁷⁵/₄   -  3.75b  + 195  = 0
- 3.75b =  - 195   - 168.75
 - 3.75b = - 363.75 
3.75b = 363.75
b = 363.75 : 3,75
b = 97

проверим:
12x² + 97x + 195 =0
D = 97 ²  - 4*12 * 195 = 9409 - 9360 = 49 = 7²
x₁ = ( - 97 + 7) / (2*12) =  - 90/24 = -3.75
x₂ = ( - 97 - 7) /( 2*12) = -  194/24 = - 97/12 =  - 8 ¹/₁₂

Ответ:  97