黄色のマーカー部分なんですけど、 どうしてXの係数同士とＹの係数同士をかけあわせた和＝0で垂直ってことを求められるのですか？ (2直線の垂直条件って、傾きを掛け合せると-1になるやつではないかんじですか、？)

20 点と直線 例題20 2直線の関係 ・① 平面上の2直線ax-3y=-a+3 ...... ⑦, x+(a-4)y=4a-12 ...... イ を考える。ただしaは定数である。 (1) 直線⑦と①が垂直であるとき, a の値を求めよ。 このとき直線をℓ, 直線④ を m とする。 lとmの交点Aの座標を求めよ。 n (2) 直線⑦と①が一致するとき, a の値を求めよ。 また, この直線をnとする。 と(1)の点Aの距離を求めよ。 (3) (1)のℓ, m と(2)のnで囲まれた図形の面積を求めよ。 解法へのアプローチ (1) 2直線の垂直条件を利用する。 ①については,αキ4 のときしか傾きを考えられないので,傾き を求める方法では場合分けが必要となるので,直線の一般形における垂直条件を利用する。 (2) 直線が一致するには,平行でなければならない。そこでまず, 2直線の平行条件を利用する。 (3) 3直線l,m,nで囲まれた図形は三角形であり、直線nを底辺とみると,点Aと直線nとの距 離が高さとなる。 20 150 [10 日本大]*| 解答 (1) 直線⑦と①が垂直であるための条件は α・1+(-3)(α-4)=0 より a=6 このとき, l: 2x-y=-1, m:x+2y=12となり, A (2,5) (2) 直線アとイが一致するためには、まず平行でなければならないから a(a−4)-1(-3)=0 a²-4a+3=0 (a-1)(a-3)=0 よって, α = 1,3 α=1のとき ア : x-3y=2, イ: x-3y=-8 α=3のとき ア : x-y=0, ①: x-y=0 したがって,直線⑦と①が一致するのは,α=3 + このとき,n:x-y=0 であり、直線と点Aの距離は |25| √1² + (−1)² 2 (3) lとnの交点をB, m n の交点をCとすると B (-1,-1), C (4, 4) であるから BC=√(4+1)^2+(4+1)=5√2 3√2+3)x-(2+a)=2-9a¹a y el 30 50 1 Aコー ------- 02 n ( m x

（2）についてです。なぜ100円4枚は50円8枚として考えるののかが分かりません。教えて欲しいです。

*35 次の硬貨を全部または一部使って,ちょうど支払うことができる金額は何通り あるか。 (1) 10円硬貨 5枚 100円硬貨3枚 500円硬貨3枚 / (2) 10円硬貨 2枚 50円硬貨3枚 100円硬貨4枚 -ヒント 350円は除くことに注意する。 (2)100円 4枚は50円 8枚と考える。

付箋の貼ってるところのadults bornのところがよくわかりません。born はbe動詞と一緒に使いませんか？

やや難 例題 次の文章はある報告書の一部である。 この文章と図を読み、問1~4 ] に入れるのに最も適当なものを,それぞれ下の①~④のうち から一つずつ選べ。 Magnet and Sticky: A Study on State-to-State Migration in the US (1) Some people live their whole lives near their places of birth, while V-F Q Vi others move elsewhere. A study conducted by the Pew Research Center (looked into the state-to-state moving patterns of Americans.) The study zens examined each state (to determine how many of their ad have moved there from othe these residents) are called "ma es of study also s both S investigated what percent of adults born in each state are still living there.) States high in these numbers are called "sticky" states. The study were magnet and sticky, while others were found that some states neither. There were also states that were only magnet or only sticky. (2) Figures 1 and 2 show how selected states rank 6n magnet and sticky scales respectively. Florida is a good example of a state that ranks high on both) Seventy percent of its current adult population was born in another state; at the same time, 66% of adults born in Florida are still living there. (On the other hand, West Virginia is neither magnet (only 27%) nor particularly sticky (49%). (In other words, it has few newcomers, and relatively few West Virginians stay there. Michigan is a typical example of a state which is highly sticky, but very low magnet, (In contrast, Alaska, which ranks near the top of the magnet scale, is the Vi least sticky of all states. S V VA (3) Three other extreme examples also appear in Figures 1 and 2. The first is Nevada, where the high proportion of adult residents born out of Svi CL V+ 9 V₁ state makes this state America's top magnet. New York is at the opposite end of the magnet scale even though it is attractive to immigrants from other nations The third extreme example is Texas, át the opposite end of the sticky scale from Alaska. Although it is a fairly weak magnet, Texas SV₁ is the nation's stickiest state.

There are many ( ) in Okinawa. We can read books and study there. ( )の中に何が入るか分かりません😢

この問題はどうやってときますか？

| 次の問いに答えなさい。 (1) 右の図について, 点 A を通るこの円の直径を作図し なさい。 A

誰か教えてくださいませんか？

① 次の英文の空所に入れるのに最も 1. I could tell from her face that she was just ( 1 giving up 2 pretending 3 enjoying 2. I have been ( 1 considering 3 planning ) studying abroad next year. 2 hoping 4 pretending ) to like him. 3 4 putting off 3. Don't forget (bille ) this medicine before you go to bed. 1 take 2 taken to take 4 taking

ここの問題の答えが欲しいです教えてくださった方フォローいいねベストアンサーします！

2〈一般動詞の間接疑問〉 次の各組の文がほぼ同じ内容を表すように, How do you go to school? I want to know that. I want to know how Ty uv (2) Why does she study English so hard? Do you Do you know why Where did you see the bird? I want to know that. towa You I want to know where (3) (1) { (5) (6) the bird. - (4) What does he have in his bag? His mother doesn't know that. His mother doesn't know what to school. know that? 200 English so hard? に適する語を書きなさい。 How many cakes did she make? I don't know that. I don't know how many cakes Which book do you want to read? I want to know that. I want to know which book byr valq vor ob stan wo ob un ob mod W (1) adi 00 02 in his bag. to read. abob HO wad word oy ol hoow 1

分からないので教えてください🙇‍♀️

3 ダイズを,面積が1m²で日当たりなどの条件が同じ2つの土地 (AとB) で栽培した。 01Aでは50粒の種子を, Bでは500粒の種子をまいた。 半年後,Aで生育したダイズの総重 量を量ると1000gであった。なお,A,Bともにすべての種子が発芽し,それらは半年 間枯れることがなかったものとする。 (1)Bにおいて,播種から半年後の1株 (1粒の種子から生じた植物体) 当たりの平均重 量は何g となるか。 (2) Aに50粒ではなく, 100粒のダイズを播種した場合, 播種から半年後の植物の総重量 は何gとなるか。

解き方が分からないので教えて頂きたいです💦

3(7+11) 540 2 自然数 15,40nの最大公約数が 5で最小公倍数が600である。 このようなnは 個あり, 最小のnは 最大のnは である。

解説してもらえませんか？

あと 次は,中学生のタケシ ( Takeshi) が書いたスピーチの原稿 の1~6の問いに答えなさい。 I am going to talk about my interesting experience. I went to London during this summer vacation with my family. This was my first trip to a foreign country. I wanted to know about London, so I looked for information about it on the Internet. I was able to see many famous things on the Internet before the trip. In London, we went to some popular places, for example, Buckingham Palace and Tower Bridge. I already saw them on the Internet, but they looked bigger and more beautiful to me when I saw them directly. I was ( )! When I walked around, I saw a lot of people from different countries, too. Then, we went to a restaurant to eat local dishes. They were very new to me, but I enjoyed them. When we finished our dinner and left the restaurant at about nine in the evening, I found 2one strange thing. It was not dark outside! I was very surprised. In Fukuoka, it is dark at nine in July, but it is not in London! This was the most interesting thing to me. I enjoyed this trip very much because I was able to discover new things. After the summer vacation, I told my classmates about my trip to London in an English class. Many of them liked my story and I was glad. After school, one of my classmates came to me and said, "I really enjoyed your story. I love Harry Potter, and I'm very interested in London. Can you tell me more about your trip ?" In fact, 3 was surprised when she came to talk to me. Before that, we didn't talk, and I though she was not interested in foreign countries. But that was not right. She knew a lo about London. We talked about my trip and Harry Potter. When we were talking she said to me, "Going abroad is a good way to study, but I have ( ) to Foreign country. I was glad to talk with you." I discovered new things about her o hat day. ) ( 4 You can get information about many things on TV and the Internet, and you ofte hink you know about people around you before talking to them. But you can discove ew things when you experience something directly. I want to remember this idea ar xperience a lot of things in the future. 主) foreign: 外国の Buckingham Palace: バッキンガム宮殿 Tower Bridge: タワーブリッジ directly : 直接に local dishes : その土地の料理 outside: 外で discover : 発見する Harry Potter: ハリー・ポッター