Verified answer

Verified answer

1) (x-4)/5 < (2x+4)/9 + 9

(x-4)/5 < (2x+4+81)/9

9(x-4) < 5(2x+85)

9x - 36 < 10x + 425

-425 - 36 < 10x - 9x

x > - 461

2) (x+17)/5 <= 3(x-5)/4

4(x+17) <= 15(x-5)

4x + 68 <= 15x - 75

68 + 75 <= 15x - 4x

11x >= 143

x >= 13

Сделано в уме, без калькулятора!