题干

如图,某小区规划在一个长30m、宽20m的长方形土地ABCD上修建三条同样宽的通道,使其中两条与AB平行,另一条与AD平行,其余部分钟花草,要使每一块花草的面积都为78cm2,那么通道宽应设计成多少m?设通道宽为xm,则由题意列得方程为(  )

A:(30﹣x)(20﹣x)=78 

B:(30﹣2x)(20﹣2x)=78

C:(30﹣2x)(20﹣x)=6×78

D:(30﹣2x)(20﹣2x)=6×78

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答案(点此获取答案解析)

C

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    Want to be happy and enjoy your life? Here are four ways to bring you happiness.

● Share appreciation

    Tell someone how much you appreciate(欣赏)them. Thank them sincerely for being part of your life. ____. When you share with someone your appreciation, they will not forget you.

●____

    One of the best ways to strengthen new ideas in your mind is to share them with others. The more often you share what you've learned, the stronger that information will become in your memory. Sharing knowledge also provides solutions to problems. The more knowledge we share, the more knowledge we receive in return.

● Share friendship

    Let your friends know that you are willing to be there when they need you. Introduce two friends who don't know each other. ____.

● Share experience

    Keep written or photo journals of your life. ____. Share a happy memory. Also share the difficult times that have helped you become stronger and wiser. When shared, the value of these experiences multiplies.

    ____. We make a living by what we get, but we make a life by what we give.

 A. Share knowledge and ideas.

 B. Record successes and failures.

 C. We succeed with the help of others.

 D. Happiness is not so much in having as sharing.

 E. You can spend time with the people that you love.

 F. Feeling appreciated is one of the most important needs that people have.

 G. If you'd like to have many friends, share friendship with others generously.