Solve the following `-30/(x - 4) <= (4x + 7)`

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We have to solve the inequality: `-30/(x - 4) <= (4x + 7)`

`-30/(x - 4) <= (4x + 7)`

=> `-30 <= (x - 4)(4x + 7)`

=> `-30 <= 4x^2 - 16x + 7x - 28`

=> `4x^2 - 9x + 2 >= 0`

=> `4x^2 - 8x - x + 2 >= 0`

=> `4x(x - 2) - 1(x - 2) >= 0`

=> `(4x - 1)(x - 2) >= 0`

This is possible if either both `4x - 1>= 0 and x - 2 >= 0` or `4x - 1<=0 and x - 2 <= 0`

=> `x >= 1/4 and x >= 2` or `x<= 1/4 and x <= 2`

The values of x satisfying this lies in (-inf. 1/4]U[2, inf.)

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