\(\frac{3}{x}+\frac{y}{2}=\frac{1}{16}\)

=>\(\frac{6+xy}{2x}=\frac{1}{16}\)

=>16(xy+6)=2x

=>8(xy+6)=x

=>8xy-x=-48

=>x(8y-1)=-48

=>(x;8y-1)∈{(1;-48);(-48;1);(-1;48);(48;-1);(2;-24);(-24;2);(-2;24);(24;-2);(3;-16);(-16;3);(-3;16);(16;-3);(4;-12);(-12;4);(-4;12);(12;-4);(6;-8);(-8;6);(-6;8);(8;-6)}

=>(x;8y)∈{(1;-47);(-48;2);(-1;49);(48;0);(2;-23);(-24;3);(-2;25);(24;-1);(3;-15);(-16;4);(-3;17);(16;-2);(4;-11);(-12;5);(-4;13);(12;-3);(6;-7);(-8;7);(-6;9);(8;-5)}

=>(x;y)∈{\(\left(1;-\frac{47}{8}\right);\left(-48;\frac14\right);\left(-1;\frac{49}{8}\right);\left(48;0\right);\left(2;-\frac{23}{8}\right);\left(-24;\frac38\right);\left(-2;\frac{25}{8}\right);\left(24;-\frac18\right);\left(3;-\frac{15}{8}\right);\left(-16;\frac12\right)\) ; \(\left(4;-\frac{11}{8}\right);\left(-12;\frac58\right);\left(-4;\frac{13}{8}\right);\left(12;-\frac38\right);\left(6;-\frac78\right);\left(-8;\frac78\right)\) ; \(\left(-6;\frac98\right);\left(8;-\frac58\right)\) }

có cạnh đáy không bạn ơi

A)vì tam giác ABC là tam giác cân

AB=BC=8

chu vi tam giác ABC=AB+AC+BC=8+5+8=21

B)vì tam giác ABC là tam giác cân

AB=BC=25

chu vi tam giác ABC=AB+AC+BC=25+12+25=62

28D

29C

30C

31B

a: =căn 16/5*36/5*49=7*4*9/5=252/5

b: =căn 250*2,5=căn 625=25

c: =căn 3/2*2/3=1

d: =5*căn 2*7*căn 2=70

C

\(SO_2+H_2O⇌H_2SO_3\)

\(K_2O+H_2O\rightarrow2KOH\)

\(BaO+H_2O\rightarrow Ba\left(OH\right)_2\)

\(SO_3+H_2O\rightarrow H_2SO_4\)

(1)          5/2 x (3/4 - 1/3) -11/12+1/4 = 5/2 x (9/12-4/12) -11/12 +3/12=5/2 x 5/12 -11/12 +3/12 = 25/24 - 11/12 +3/12=25/24 -22/24 +                           6/24=9/12=3/4

(2)           11/12 : (4/10 + 3/5) + (5/6 - 1/2) x2/3 

                = 11/12 : (4/10 + 6/10) + (5/6-3/6) x 2/3

                = 11/12:1 +1/2 x 2/3

                = 11/12 + 2/3 =11/12+8/12 = 19/12