啓林館：未来へ広がる数学１

p.88 問1\(\begin{split}&180{\, \small \times \,} 4+480
\\[2pt]~~=~&720+480
\\[2pt]~~=~&1200
\end{split}\)

p.88 問2\(~~~\)(イ)、(ウ)

p.89 問3\(~~~\)いえる

p.90 問4\(\begin{split}{\small (1)}~x=12\end{split}\)　　\(\begin{split}{\small (2)}~x=-2\end{split}\)
\(\begin{split}{\small (3)}~x=1\end{split}\)

p.91 問5\(\begin{split}{\small (1)}~x=8\end{split}\)　　\(\begin{split}{\small (2)}~x=-4\end{split}\)
\(\begin{split}{\small (3)}~x=-1.2\end{split}\)

p.91 問6\(\begin{split}{\small (1)}~x=21\end{split}\)　　\(\begin{split}{\small (2)}~x=-20\end{split}\)
\(\begin{split}{\small (3)}~x=-12\end{split}\)

p.91 問7\(\begin{split}{\small (1)}~x=9\end{split}\)　　\(\begin{split}{\small (2)}~x=-6\end{split}\)

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\(\begin{split}{\small (3)}~x=\frac{\,1\,}{\,3\,}\end{split}\)

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p.91 練習問題 1\(\begin{split}{\small (1)}~x=26\end{split}\)　　\(\begin{split}{\small (2)}~x=-4\end{split}\)
\(\begin{split}{\small (3)}~x=23\end{split}\)　　\(\begin{split}{\small (4)}~x=8\end{split}\)
\(\begin{split}{\small (5)}~x=-3\end{split}\)　　\(\begin{split}{\small (6)}~x=5\end{split}\)
\(\begin{split}{\small (7)}~x=15\end{split}\)　　\(\begin{split}{\small (8)}~x=-6\end{split}\)
\(\begin{split}{\small (9)}~x=-10\end{split}\)　　\(\begin{split}{\small (10)}~x=-3.5\end{split}\)

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\(\begin{split}{\small (11)}~x=-60\end{split}\)　　\(\begin{split}{\small (12)}~x=-\frac{\,3\,}{\,4\,}\end{split}\)

p.92 問1\(\begin{split}{\small (1)}~x=3\end{split}\)　　\(\begin{split}{\small (2)}~x=-2\end{split}\)
\(\begin{split}{\small (3)}~x=-1\end{split}\)　　\(\begin{split}{\small (4)}~x=2\end{split}\)

p.93 問2

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\(\begin{split}{\small (1)}~x=-2\end{split}\)　　\(\begin{split}{\small (2)}~x=\frac{\,15\,}{\,2\,}\end{split}\)

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\(\begin{split}{\small (3)}~x=5\end{split}\)　　\(\begin{split}{\small (4)}~x=-1\end{split}\)

p.93 問3\(\begin{split}{\small (1)}~x=3\end{split}\)　　\(\begin{split}{\small (2)}~x=-1\end{split}\)

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\(\begin{split}{\small (3)}~x=\frac{\,1\,}{\,2\,}\end{split}\)　　\(\begin{split}{\small (4)}~x=0\end{split}\)

p.94 問4\(\begin{split}{\small (1)}~x=5\end{split}\)　　\(\begin{split}{\small (2)}~x=9\end{split}\)

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\(\begin{split}{\small (3)}~x=2\end{split}\)　　\(\begin{split}{\small (4)}~x=\frac{\,4\,}{\,7\,}\end{split}\)

p.95 問5\(\begin{split}{\small (1)}~x=8\end{split}\)　　\(\begin{split}{\small (2)}~x=-6\end{split}\)

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\(\begin{split}{\small (3)}~x=3\end{split}\)　　\(\begin{split}{\small (4)}~x=\frac{\,5\,}{\,2\,}\end{split}\)

p.95 話しあおう\(\begin{split}{\small (1)}~x=-2\end{split}\)　　\(\begin{split}{\small (2)}~x=3\end{split}\)
\(\begin{split}{\small (3)}~x=3\end{split}\)　　\(\begin{split}{\small (4)}~x=-1\end{split}\)

p.96 練習問題 1\(\begin{split}{\small (1)}~x=7\end{split}\)　　\(\begin{split}{\small (2)}~x=1\end{split}\)
\(\begin{split}{\small (3)}~x=10\end{split}\)　　\(\begin{split}{\small (4)}~x=-9\end{split}\)
\(\begin{split}{\small (5)}~x=3\end{split}\)　　\(\begin{split}{\small (6)}~x=-3\end{split}\)

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\(\begin{split}{\small (7)}~x=-6\end{split}\)　　\(\begin{split}{\small (8)}~x=\frac{\,5\,}{\,2\,}\end{split}\)

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\(\begin{split}{\small (9)}~x=50\end{split}\)　　\(\begin{split}{\small (10)}~x=-\frac{\,4\,}{\,3\,}\end{split}\)

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\(\begin{split}{\small (11)}~x=-400\end{split}\)　　\(\begin{split}{\small (12)}~x=0\end{split}\)

p.96 練習問題 2\(\begin{split}{\small (1)}~x=1\end{split}\)　　\(\begin{split}{\small (2)}~x=5\end{split}\)
\(\begin{split}{\small (3)}~x=2\end{split}\)　　\(\begin{split}{\small (4)}~x=4\end{split}\)
\(\begin{split}{\small (5)}~x=3\end{split}\)　　\(\begin{split}{\small (6)}~x=-4\end{split}\)
\(\begin{split}{\small (7)}~x=17\end{split}\)　　\(\begin{split}{\small (8)}~x=125\end{split}\)

p.98 問1

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\(\begin{split}{\small (1)}~x=12\end{split}\)　　\(\begin{split}{\small (2)}~x=\frac{\,15\,}{\,4\,}\end{split}\)

p.98 問2\(\begin{split}{\small (1)}~x=9\end{split}\)　　\(\begin{split}{\small (2)}~x=20\end{split}\)

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\(\begin{split}{\small (3)}~x=\frac{\,8\,}{\,9\,}\end{split}\)　　\(\begin{split}{\small (4)}~x=3\end{split}\)

p.98 練習問題 1\(\begin{split}{\small (1)}~x=9\end{split}\)　　\(\begin{split}{\small (2)}~x=21\end{split}\)

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\(\begin{split}{\small (3)}~x=\frac{\,4\,}{\,15\,}\end{split}\)　　\(\begin{split}{\small (4)}~x=9\end{split}\)

p.101 問1\(~~~27\) 年後

p.102 問2\(~~~480\) 円

p.103 問3\({\small (1)}~13\) 箱　　\({\small (2)}~50\) 個

p.105 問4弟は駅までの 2km＝2000m を進むのに
\(\begin{split}~~~2000{\, \small \div \,}80=25\end{split}\)
よって、25分で着く
兄は弟が家を出発して20分後に出ているので、残り5分では
\(\begin{split}~~~280{\, \small \times \,}5=1400\end{split}\)
これより 1400m＝1.4km しか進めない
したがって、兄は弟に追いつくことができない

p.105 練習問題 1　\(5\) 番

p.105 練習問題 2　\(230\) 人

p.106 問1\(~~~440~{\rm mL}\)