1) 2 1/2 : 3 3/4=5/2 : 15/4 = 5/2 *4/15 = 2/3
2) 10- 2/3=9 1/3
3) 2 1/2 - 1 1/3 =5/2 -4/3 =(15-8)/6 =7/6
4) (7/6)*6 =7
5) 9 1/3 +7 =16 1/3
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х 1 ОДЗ x≠0 6-5x≠0 x≠1,2
------- = ---------
6-5х х
х*х= 1*(6-5х)
х²= 6-5х
х²+5х-6=0
D=25+24=49
x₁=(-5+7)/2= 1
x₂=(-5-7)/2= -6
х²-7х+12
---------------- =0 ОДЗ 4х+20≠0 х≠-5
4х+20
дробь равна 0 если значение числителя равно 0
х²-7х+12=0
D=49-48=1
х₁=( 7+1)/2=4
x₂=(7-1)/2=3
(3х-2)(5х-4)=(2-3х)²
15х²-10х-12х+8 =4-12х+9х²
15х²-9х²-22х+12х+8-4=0
6х²-10х+4=0 /2
3х²-5х+2=0
D=25-24=1
x₁=( 5+1)/6= 1
x₂=(5-1)/6= 4/6 =2/3