Помогите, пожалуйста

1) (2-x)(8-x)<0

2) (1-x)(7-x)>0

3) (x-2)(5+x)>0

1) 16-2x-8x+x²<0 x²-10x+16=0D= b²-4ac = 100-64= 36x1= -b-√D -------- = 10-6 2a. ------ = 2 2 x2= -b+√D -------- = 10+6 2a. ------ = 8 2 + - +——•——•———› 2 8(-∞;2)€(8;∞) 2) 7-x-7x+x²>0 x²-8x+7=0D=b²-4ac= 64-28=36 x1= -b-√D = 8-6 =1 -------- ----- 2a. 2x2= -b+√D -------- = 8+6 2a. ------ = 7 2 +. - + ———•——•——› 1 7(-∞;1)€(7;∞) 3)5x+x²-10-2x>0 x²+3x-10=0 D=b²-4ac= 9+40=49 x1= -b-√D -------- = -3-7 2a. ------ = -5 2x2= -b+√D -------- = -3+7 2a. ------ = 2 2 + - +———•————•———› -5 2(-∞;-5)€(2;∞)