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数学 中学生

(3)の丸をつけたところのようになるのはなぜですか?関数の差の計算方法を教えて下さい!座標が高い方から下を引くのでしょうか?

********************* [8-15] 右の図のように, 放物線y=xと直線y=4との交点を点A,Bとし, 放物線 y=ar (a<0) と直線y=-8との交点を点C, D とする。 直線ACはy=mxである。 また、放物線y=ax(a<0) 上を原点Oから点Dまで動く点Pがある。 次の各問に答えよ。 (1) 点のx座標を求めよ。 (2) mの値とαの値を求めよ。○○ (3) △OAB と PCDの面積が等しくなるときの点Pの座標を求めよ。 (4) APABと△PCDの面積の和が30となるときの△PCDの面積を求めよ。 (0 E-D),501 D E-D=1- ol ARSE & Py *************************************************************************** (1) 点Aのy座標は4だから, y=xにy=4を代入して,4=x 点のx座標は負の数なので, 2 材材本体******☆☆☆ [福岡大学附属大濠] (2) 直線y=mxは点Aを通るから, (-2,4)を代入して, 4=-2m 直線ACの式はy=-2xで,点Cのy座標は-8だから, よって,C4, -8) y=ax² に代入して, -8=a×42 JOSTED 210 p=-5 SALAN Dc019 -8 A B A1 a=-2 ****** x= ±2 0=0+00=²0 Jet 6-8-005 po ****************** m=-2 -8=2xx=4r-a] HQERSAR (D). (3) △OABの面積は1/12 ×AB×4=1/2×4×4=8点Pから 点PからCDに垂線PHをひくと, APCD=121×CD×PH=1/2×8×PH これが8になればよいのだから,PH = 2 ) したがって, 点Pのy座標は, -8+2=-6 これをy=-12 x に代入して, -6= =-1²x²x²=12 x<0°C, x=-√12=-2√3 P(−2√3, −6) A✯ (1) Ad 2- =(-x) (5+x) 10-0-x-2 (4) APAB+△PCD=30のとき, △PAB, △PCDの底辺をそれぞれAB, CDとみると,高 SAS SAS さは点PからAB, CDまでの距離となる。 点Pのy座標をpとすると, APAB+△PCD=1/123× =1/21×4×4-P +1/1/2×8×I-(-8)=30 8-2p+4p+32=30 45 of 164476 よって, PCD=1/2×8×1-5-(-8)}=12 第8

未解決 回答数: 1
英語 中学生

この答えあっていますか? 1、Futoshi is often go to river 2、Hi give to yukata 英語苦手です…

7 これを読んで、後の問いに答えなさい。 次の英文は、 Futoshiがホームスティを体験したことについて書かれた文章です。 Futoshi is a junior high school student. Last summer he went to New Zealand for two weeks to study English. He stayed with a family there. They were Mr. and Mrs. Green and their son, Tom. Tom was as old as Futoshi. One day, at breakfast, Tom said. "Fishing is very popular in New Zealand. Do you like to go fishing, Futoshi?" Futoshi said, "Yes, I often go fishing with my family in Japan." Then Mr. Green said, "That's good. We have a boat) Do you want to go fishing with us in the sea tomorrow, Futoshi?" Futoshi said, "Yes. I often go fishing in the river and the lake, but not in the sea. I really want to do that with you. Thank you." The next day, Futoshi went fishing with Tom and his family on the boat. The weather was very good. There were no clouds in the blue sky and the sun was (shining. And the sea was blue and clear. Everything was so beautiful. Futoshi felt very happy. Tom said, "Look, Futoshi. Some dolphins are swimming over there." Futoshi said, "Wow, greatl This is my first time to see dolphins in the sea. It's so exciting!" Then Mr. Green said, "OK. Let's start fishing now." Tom and his After about twenty minutes, Futoshi got a big fish. He said, "Oh, this is very big. I have never got a big fish like this." Tom said, "You are great, Futoshi." family also got some fish. At lunch time, Mr. and Mrs. Green cooked some of the fish they got. Under the blue sky, Futoshi ate them with his host family on the boat. One night, Futoshi showed a yukata to Tom and his family. Futoshi said. "This is a present for Mrs. Green. It is a traditional Japanese dress called yukata in Japanese. Yukata is a kind of kimono. You can see a lot of people in yukata at summer festivals in Japan." Futoshi taught her how to put on the yukata. When she put on the yukata, she said, "How do I look? Futoshi said "You look beautifull" And then she said, "This is nice, but it's difficult for me to walk in this yukata." (1) 次の①、②の問いに、英語で答えなさい。 Where did Futoshi often go fishing in Japan? What was given to Mrs. Green by Futoshi?

解決済み 回答数: 1