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数学 高校生

(2)の問題なんですけど、 「このとき、Y=5m+2」が出てくるのが分からないので教えて頂きたいです🙏

例題 次の各問いに答えよ。 1 1 1 (1) 等式 + 3 y x 16 不定方程式の解法 となる自然数の組(x, y) で x≧y を満たすものを [13 1 求めよ。 (2) x,yを1以上,100 以下の整数とする。 5x-7y=1 をみたす (x, y) は [13 何組あるか。 解法へのアプローチ (1) 分母を払って,(x-a)(y-b)=cの形に変形すれば,左辺の因数はcの約数になる。 (2) 方程式の一般解を求めて, 1≦x, y≦100 を満たすものを数える。 解答 (1) 等式の両辺に 3xy を掛けて分母を払うと 3y+3x=xy xy-3x-3y=0 これより (x-3)(y-3)=9 ここで, x-3, y-3は9の約数であり,x,yはx≧y を満たす自然数だから x-3≧y-3≧-2 したがって (x-3, y-3)= (9, 1),(3,3) よって (x,y)=(12,4),(6,6) 5x-7y=1 ・・・① の解の1組を求めて 5・37・2=1 (2) ①と②の辺々を引いて 5(x-3)-7(y-2)=0 つまり 5(x-3)=7(y-2) ここで5と7は互いに素であるから, x-3は7の倍数である。 したがって,mを整数として x-3=7m すなわち x=7m+3 このときy=5m+2 1≦x≦100 より 1≦7m+3≦100 ..... ... ③ == Conf 97 sms 7 これを満たす整数mは、m=0,12, 13 の全部で14個ある。 また,これらの m の値に対して, ③のyの値は 1≦y≦100 を満たしている よって、求める (x, y) の組は, 14組 = 13.8...

解決済み 回答数: 1
英語 高校生

過去完了のalwaysは「昔からずっと」という意味だと思っていたのですが、解答では「それまでは」と書いていました。「それまでは」とはつまり「今は違う」ということでしょうか? また過去の出来事でのnowは「その時点を表す」という意味なので「そのとき」と訳せばいいと思っていたの... 続きを読む

1 演習 1 (問題→本冊: p.3) Sally had lived abroad most of her life, but at last she came back to England to live. She had always loved trees and flowers, and now she aimed to buy a small house in the country with a garden. 【全文訳】 サリーは人生の大方の期間, 外国暮らしをしていたが,ついにイギリスで暮 らそうと戻って来た。(それまでは)いつも木と花を愛していて, これから田舎に庭 付きの小さな家を買おうとした。 【解説】 述語動詞は had lived (過去完了), came (過去時制), had loved (過去完了), aimed (過去時制)。 (for) most of her life 「彼女の人生のほとんどの期間」は had lived を修飾, to live は副詞的用法 (目的) 「暮らすために」 で, came back 「戻った」 を修飾。 第2文の後半の now は物語の中などで 「今や, そこで」 の意味。 with a garden は GER house を修飾して 「庭のある家」。 came, aimed の2つの過去時制が 「基準時」 ( 19 課)。

未解決 回答数: 1
英語 高校生

間違ってるとこあったら教えてください

英語 7 次の英文を読み、1から4の ちから一つずつ選びなさい。 解答番号は 内に入れるのに最も適当なものを,それぞれ①~④のう 27 O others. 24 Nagisa was a nurse who was working in Zimbabwe, a country in Africa. One day, she got an email from her old high school homeroom teacher, Mr. Tamai. He wanted to ask was hesitant at first because she always had a fear of public speaking, she felt this would be a Nagisa to give his students a talk about what she was doing in Zimbabwe. Although Nagisa good chance to tell students about the joy of working abroad and helping people in need. The next time Nagisa went back to Japan, she visited Mr. Tamai's high school to speak with his students. She was very nervous, but to her relief, the students seemed to be very interested in her story. She talked about her job, her reasons for working in Zimbabwe, and both some good and bad things about working there. She shared her passion for helping After the talk, one of the students came to talk to Nagisa. He said, "I would like to work abroad and help people in the future like you, but I don't know what kind of job I would be able to do. Do you have any advice for me?" Nagisa said, "I think, doing something you like is the key. Keep doing it, and doors will open for you." (Ten years later) One sunny day, a group of Japanese farmers visited the village where Nagisa was living. They came to teach local people how to grow plants and vegetables. People in the village were eager to learn from them. Then, the youngest member of the farmers' group came to talk to Nagisa and said, "Hi, do you remember me? You gave a talk at my school ten years. ago. At that time, I liked growing plants and vegetables, but I didn't know how to use that to help others. You told me to keep doing what I liked and that has really opened doors for me to do what I'm doing now. Thank you." Hearing his words, Nagisa recognized who the young man was. She was surprised and pleased that her talk from ten years before was able to make a difference in this young man's life. 1 Nagisa was 24 a high school teacher. 2 afraid of public speaking. 3 scared of living abroad. 4 a doctor in Zimbabwe. 4 2 One thing Nagisa told Mr. Tamai's students was why she chose to work in Zimbabwe. how she learned a new language. 3 when she went to a high school in Africa. 4 what she did to impress local people. 3 One of the students said he wanted G (2) (3 to be a kind nurse like Nagisa. to teach Japanese culture in Africa. to open doors for other people. to help people overseas. 26 3 25 4 Ten years after her talk, Nagisa 27 made an appointment to meet one of her old friends in Africa. 2 became a farmer and taught local people how to grow vegetables. met one of Mr. Tamai's students again. 4 4 gave a small talk in her high school again.

未解決 回答数: 1