1. 15 - 2x = 9
2х = 6
х = 3
2. 6/4x-54 = 1/49
4x-54 =294
4x = 240
x = 60
3. 2x+5/3 = 25
2x+5 = 15
2x = 10
x = 5
4. -72-17x = x^2
x^2+17x+72 = 0
x1+x2 = -17 x1=-8
x1*x2 = 72 x2=-9 - наименьший корень
5. 3x-8 =25
3x = 33
x = 11
6. x-4 = 27
x = 31
7. 1/15-4x = 4/100
60-16x = 100
16x = -40
x = -24
8. 1/5-2x = 1/9
5-2x = 9
2x = -4
x = -2
9. 6+5x = x^2
x^2-5x-6 = 0
x1+x2 = 5 x1 =6
x1*x2 = -6 x2 = -1 - наименьший корень