Предмет: Математика, автор: KSshA2011

Ширина прямоугольника 23 см. На сколько увеличится площадь этого прямоугольника, если его длину увеличить на 3 см?
В ответ запишите только число - величину изменения площади прямоугольника в квадратных сантиметрах.

Ответы

Автор ответа: d1vanpokrashen
1

Ответ:

34,5 см²

Пошаговое объяснение:

Допустим мы имеем прямоугольник, у которого ширина 23 см, а длинна 10 см.

Площадь такого прямоугольника будет 230 см²

Теперь прибавим к его длине 3 см, то есть по 1,5 см к двум противолежащим сторонам, например к сторонам которые по 10 см.

У нас получится прямоугольник у которого ширина 23 см, а длинна 11,5 см.

Площадь такого прямоугольника будет 264,5 см²

Теперь посчитаем разницу между площадями этих прямоугольников:

264,5 - 230 = 34,5 см²


KSshA2011: Мне нужно просто число
KSshA2011: И в задаче вопрос был На сколько увеличится площадь этого прямоугольника
d1vanpokrashen: Просто число 34,5. Я же написала в графе ответ. В чем проблема?
KSshA2011: Эх
KSshA2011: Без ,5
d1vanpokrashen: Почему? Я правильно решила. Посчитайте сами на калькуляторе 23*11,5 = 264,5.
KSshA2011: Извени да сорян
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1. GRAMMAR

А). Underline the correct item (5 scores)

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3). Mum wakes up at 7 o’clock ……the morning.

4). Brian and Steve play football…..Mondays.

5). I see my friends…..the weekend.

C). Choose and underline the correct verb (5 scores).

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a) ate b)eats c) is eating

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2. Are you interested … history as well?

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1. friends/ food/ your/ traditional/ eating/ Are?

2. Linda / on/ Sundays/ her/ visits/ granny.

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3. WRITING

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Use her letter as an example.

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