a)
- \frac{2x-1}{9}- \frac{4x-5}{15}=x-5
- \frac{2x-1}{9}- \frac{4x-5}{15}-x=-5 /*(-45)
5(2x-1)+3(4x-5)+45x=225
10x-5+12x-15+45x=225
67x-20=225
67x=245
x=\frac{245}{67}
x=3\frac{44}{67}
b)
(x+1)(x+8)=(x+3)(x-2)
x^2+8x+x+8=x^2-2x+3x-6
x^2+9x+8=x^2+x-6
x^2+9x+8-x^2-x=-6
8x=-6-8
8x=-14
x=\frac{-14}{8}=-\frac{7}{4}
x=-1\frac{3}{4}
c)
(x- 4)^2 -1=(x-3)(x-2)
x^2-8x+16-1=x^2-2x-3x+6
x^2-8x+15=x^2-5x+6
x^2-8x+15-x^2+5x=6
-3x=6-15
-3x=-9 /:(-3)
x=3