Overview: 1 questions will be solved this time.Among them
           ☆1 inequalities

[ 1/1Inequality]
    Assignment:Find the solution set of inequality (900+4*a)/(1200+3*a)     Question type: Inequality
    Solution:
    The inequality can be reduced to 1 inequality：
         ( 900 + 4 * a ) / ( 1200 + 3 * a ) < a / 300         (1)
        From the definition field of divisor
         1200 + 3 * x ≠ 0        (2 )

---

    From inequality(1)：
         a < -300
    From inequality(2)：
         a < -400 或  a ＞ -400

---

    From inequalities (1) and (2)
         a < -400 或  -400 < a < -300     (3)

---

    The final solution set is :
         a < -400 或  -400 < a < -300

Your problem has not been solved here? Please take a look at the  hot problems ！