Known inequality (MX)_ 1) The solution set of (x + 2) > 0 is - 3

Known inequality (MX)_ 1) The solution set of (x + 2) > 0 is - 3

When x = - 2, (MX-1) (x + 2) = 0 is not consistent with (MX-1) (x + 2) > 0
When x = - 3 (- 3m-1) * - 1) > 0
3m+1＞0
m＞-1/3

If M < 0, then the solution set of the inequality MX + n < 0 is ()
A.x＞-n/m B.x＜-n/m
C.x＞n/m D.x＜n/m
Explain why

mx+n＜0
MX ＜ - n shift term first
And because m < 0,
So both sides of the X ＞ - N / M inequality are multiplied by a negative number at the same time to change the sign
So the answer is a

The inequality | mx-2 | MX m | about X is known to be greater than or equal to 5
I when m = 1, find the solution set of this inequality

M = 1 is substituted into the original formula to get X-2 | + | x + 1 | ≥ 5 1) when x ≥ 2, the absolute value of the original formula is X-2 + X + 1 ≥ 5 2x ≥ 6 x ≥ 3, i.e. x ≥ 3 2) when - 1 ≤ x < 2, the absolute value of the original formula is 2-x + X + 1 ≥ 5 3 ≥ 5, which is not true. 3) when x < 1, the absolute value of the original formula is 2-x-x-1 ≥ 5 2x ≤ - 4 x ≤ - 2, i.e. x ≤ - 2 1) 2) 3), the solution set of the inequality is {x | x ≤ - 2 or X ≥ 3}