Постройте график функции y=-x^2-4x. при каких значениях x функция принимает значения , меньшие 3?

1) a/16 + x/16 =(a+x)/16

2) 5m/n - 3m/n =2m/n

3) 3x +4y/12 - x+2y/12 =2x+6y/12=2x+y/2

4) a+2b/2c - a-4b/2c =b/c-2b/c=-b/c

5) a-8/a^2-25 + 13/a^2-25 =a-8/(a+5)*(a-5)

6) 5x+1/2 - x/2 =9x/2+1/2=4,5x+1/2

7) a+3/4 - a+1/4 =4/4=1

8) 2x/a-b - x/b-a =2x/a-b + x/a-b=3x/a-b

9) a/x-1 + b/1-x =a/x-1 - b/x-1=a-b/x-1

10) a-5/a-3 + a+5/3-a =a-5/a-3 - a+5/a-3=(a-5)*(a+5)/a-3=(a^2-25)/a-3

11) 3x-2/5 + 5x-3/3 =(9x-6+25x-15)/15=(24x-21)/15=3*(8x-7)/15=(8x-7)/5

12) 2m+5/6 - m-a/8 =m+(20-6a)/24=m+2*(10-3a)/24=m+(10-3a)/12

13) 7/10a -5/4a =(70-25)/20a=45/20a=9/4a

X(x-3)(x-1)(x-2)-24=0
 
   x²-3x=t
     t(t+2)-24=0
    t²+2t-24=0
   D=4+4*24=100=10²
 t=(-2+10)/2=4                                                        t=(-2-10)/2=-6
 x²-3x=4                                                                  x²-3x=-6
 x²-3x-4=0                                                               x²-3x+6=0
D=9+16=25                                                            D=9-4*6<0        
x=(3+5)/2=4     x=(3-5)/2=-1                                     x∈∅

ответ: x=4; x=-1