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16 tháng 6 2020
58. They used to study well
59. Although it was raining hard , he wanted to go out
60. They wish they could become soccer players
61. He told Ba that he was happy then
62. No girl in my class is as smart as her
63. She told her son not to be lazy
64. Because Lan was tired , she didn't go out
65. My sister doesn't like fast food
TD
1
LT
0
RQ
3
AH
Akai Haruma
Giáo viên
24 tháng 12 2018
Lời giải:
Vì \(3x=5y\Rightarrow y=\frac{3}{5}x=0,6x\). Thay vào điều kiện thứ 2 ta có:
\(2x+3y=-39\)
\(\Leftrightarrow 2x+3.0,6x=-39\)
\(\Leftrightarrow 3,8x=-39\Rightarrow x=\frac{-195}{19}\)
\(\Rightarrow y=0,6x=0,6.\frac{-195}{19}=\frac{-117}{19}\)
Vậy \((x,y)=(\frac{-195}{19}; \frac{-117}{19})\)
S
24 tháng 12 2018
Ta có: \(3x=5y\Leftrightarrow\dfrac{x}{5}=\dfrac{y}{3}\Leftrightarrow\dfrac{2x}{10}=\dfrac{3y}{9}\)
Áp dụng tính chất dãy tỉ số bằng nhau:
\(\dfrac{2x}{10}=\dfrac{3y}{9}=\dfrac{2x+3y}{10+9}=\dfrac{-39}{19}\)
\(\Leftrightarrow\left\{{}\begin{matrix}\dfrac{x}{5}=\dfrac{-39}{19}\\\dfrac{y}{3}=\dfrac{-39}{19}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{-195}{19}\\y=\dfrac{-177}{19}\end{matrix}\right.\)
Vậy, ...
19 tháng 5 2020
const fi='songuyen.txt';
fo='ketqua.txt';
var f1,f2:text;
a:array[1..100]of integer;
n,i,t:integer;
begin
assign(f1,fi); reset(f1);
assign(f2,fo); rewrite(f2);
n:=0;
while not eoln(f1) do
begin
inc(n);
read(f1,a[n]);
end;
t:=0;
for i:=1 to n do
if a[i]>0 then t:=t+a[i];
writeln(f2,t);
close(f1);
close(f2);
end.
VC
2
XD
1 tháng 8 2017
1, People believe that he was killed by terrorists.
-> It is believed that he was killed by terrorists.
-> He is believed to have been killed by terrorists.
2, We know that they live in a small flat in the fifth
-> They are said to live in a small flat in the fifth.
-> It is said that they live in a small flat in the fifth.
3, They say exericise is good for health
=> Exercise is said to be good for health.
=> It is said that exercise is good for health.
4, they have sent that money to the poor families
=>Money have been sent to be the poor families.
=> The poor families have been sent that money.
5, You need to out your hair.
=> Your hair need to be out
=> Your hair need outing.
6, He is repairing my car now
=> My car is being repaired now.
=> I am being repaired my car now.
7, Are you making tea?
=> Is tea being made?
=> Are we being made tea?
8. I usually get my mother to wash my clothes.
=> My mother is usually got to wash my clothes.
=> My clothes are usually got to wash by my mother.
9. How long have you use this bike?
=> How long has this bike been used?
=> When was this bike started to used?
10. I must leave a message.
=> A message must be left.
=> You must be received a message.
11. My father used to take to the park on Sundays.
=> The park was used to take by my father on Sundays.
=> The Sundays were used to take to the park.
12. I will be waiting for you this time tomorrow.
=> You will being waited this time tomorrow.
=> This time tomorrow will being waited for you.
13. Did you finish the work on time?
=> Was the work finished on time?
=> Was in on time finished the work?
14. I have never written a letter to my find, I friend phone.
=> A letter has never been written to my find, I friend phone.
=> My find has never been written a letter, I friend phone .
15. They are going to introduce a new style of feans next month.
=> A new style of feans is going to be introduced next month.
=> We are going to be introduced a new style next month.
16. I want you to help me.
=> You are wanted to help me.
=> Your help is wanted me.
Chúc bạn học tốt!!!
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