= - 2 + 0,6b - 6/5b + 2 = (0,6b - 6/5b) + (2 - 2) = (0,6b - 1,2b) = - 0,6b
при b = - 1/3
- 0,6b = - 6/10 * (-1/3) = 2/10 = 0,2
Ответ: 0,2.
(4x-3)(4x+3)-(3x-4)²=10x-25
1) (3x-4)²=(3x-4)(3x-4)=9x²-12x-12x+16=9x²-24x+16
2) (4x-3)(4x+3)=16x²+12x-12x-9
16x²-9-(9x²-24x+16)=10x-25
16x²-9-9x²+24x-16-10x+25=0
7x²+14x=0
7x(x+2)=0
x1=0
x2=-2